History suggests that no founder of a nation considered or solved every conceivable problem that future generations would encounter, and that effort towards finding solutions may have been ongoing. It might be difficult from our written record to make a clear case above other hypotheses that, given sufficient time and experience, the Founding Fathers would not ultimately have favored a different strategy of taxation than the de facto strategy, George Washington himself regarding the matter as an apparently necessary inconvenience. This should not prevent discovery of a correct stance given the fundamental principles they advanced.
My theory is that they may have allowed the wealth tax to exist simply as a standing expedient for the lack of apparent alternatives, or because they did not feel the people were accepting enough to advance a superior alternative during their lifetimes.
However, a wealth tax is fundamentally opposed to the tenets of classical liberalism, for the following reasons:
It disrupts individual economic freedom (in a way, without limit), while giving power to the state without any return of benefits to those affected.
Classical liberalism proponents intended to maximize individual economic autonomy, by limiting the power of the government. Forcing Uncle Sam to be on the list of one's heirs or allowing perpetual taxes against one's reserves seems to contradict economic autonomy, while aggrandizing the government purse and therefore powers without any corresponding benefit to those so taxed.
If an individual desires, in his Last Will and Testament, to bequeath all or a portion of his earthly goods to some government treasury, that is his privilege--however, presupposing that some portion of the means he has intended to consecrate for the benefit of his heirs actually belongs to the government seems like folly. To whom will the members of government be made accountable, if the fortune they are taking is from the deceased?
That speaks to inheritance taxes specifically, and now to address wealth taxes generally: they are sore fetters to freedom. A wealth tax such as a property tax generally is levied recurrently at set intervals on the basis of how much wealth or value is owned. The recurrent nature of the taxation implies mathematically that one's holdings and assets shrink exponentially towards zero over time. This is a tax against private property and ownership, and this inevitably decreases economic freedom because it discourages the edification and accumulation of worth, with the very same assets being taxed repeatedly until they have run out. In short, wealth and property taxes directly contradict the principle of private ownership of property, and nullifies such deed clauses as were common at the time, granting ownership of a property to a person, and "to his/her heirs and assigns, in perpetuity".
A wealth tax or inheritance tax is inequitable. A death in the family is a misfortune that carries economic and social disadvantages with it. A family that has a greater incidence of deaths will be taxed at a higher rate than others, making the tax a further burden on the grief of the unfortunate. Although death is inevitable together with its corresponding losses, taxing the bereaved on that occasion seems a small and uncompassionate thing to do. For the childless, donating one's estate to charity seems quite reasonable if that is according to his wishes, and if no will exists and no heir even of the remotest kin can be identified, it seems fair to reapportion the property through a dedicated trust within the government--what else is there to do in such a case? However, those families having children, especially young children, will be disadvantaged unfairly by an involuntary inheritance tax. Furthermore, those preparing against future needs are unfairly discriminated against by a wealth tax, because the larger their holdings, the more they are taxed, regardless of whether their holdings are being replenished, or not. This spells out a mistaken premise in the very existence of recurrent wealth taxes: That the Government owns your property, and it is merely on loan to you and will eventually but inevitably be repossessed.
Adam Smith was in favor of the equitableness of taxes as his first maxim of taxation:
The subjects of every state ought to contribute towards the support of
the government, as nearly as possible, in proportion to their
respective abilities; that is, in proportion to the revenue which they
respectively enjoy under the protection of the state.
Adam Smith, Wealth of Nations
To Sum Up:
All of this suggests that if property rights are to be preserved, consistent with the ethic of the Declaration of Independence and the Bill of Rights (Amendments 9 and 10, which distinctly prioritize citizens' rights as broader than governments' rights), there must be a principle of proximity and preference first to those who are nearest of kin to the deceased, then to those more distant of kin, wealth devolving into the hands of the government as a designated trust only in those rare cases when no heirs can be identified following due diligence.
The quotes you used do not seem to justify an immediate taxation of decease to augment the government, rather, it is spelled out unambiguously in Adam Smith's own view:
A power to dispose of estates for ever is manifestly absurd. The earth
and the fulness of it belongs to every generation, and the preceding
one can have no right to bind it up from posterity. Such extension of
property is quite unnatural.
And Thomas Jefferson's quote:
I set out on this ground, which I suppose to be self evident, "that
the earth belongs in usufruct to the living": that the dead have
neither powers nor rights over it. The portion occupied by an
individual ceases to be his when himself ceases to be, and reverts to
the society.
Of course we cannot and should not keep the beneficial assets of the dead unused and unoccupied throughout all time; that would seem to be the absurdity spoken of. Who is the society of the deceased? First, his own living kin, and ultimately, his local and national community if no kin or heirs can be identified. Thus, no family should be deprived of what is by right theirs to dispose of as they see fit, so long as such family or their heirs exist. The wording of property deeds hits the nail on the head: "To his or her heirs and assigns, to have and to hold, forever". Property taxes contradict this verbiage and its backing principle.
The Classical Liberal solution:
The dissolution of all recurring property taxes is the only way to limit the power of the government indefinitely and keep economic freedom in the hands of the people. We are not the property of the State; our assets belong to ourselves and to our families. A flat rate (equitable) income tax, as suggested by Adam Smith in the first of his quotes above, seems to be the only sustainable solution that respects both property rights and the apparent necessity of taxation in some form or another. A maximum of half of a tithe (5%) seems reasonable to sustain all the necessary functions of government. Income or increase is taxed only once, and so there is still incentive for growth, but once acquired, property is permanent and perpetual unless dispensed by the sole authority of the owner. "You get to keep (some very high percentage of) what you earn" is a maxim that would unleash unprecedented growth and promote savings, because there would be no holes in the bucket.
Finally, if we are going to be consistent with Washington's pleas for fiscal responsibility and not leaving debts to future generations (see my first reference), does it not make sense instead to endow them with such means as may be necessary to secure their future prosperity--seed crop, as it were--and cut out the burdensome and unnecessary federal agent commissions? Some may argue that leaving fortunes to (potentially ungrateful) children may corrupt them more than help them, but I would avow that there is no one more capably equipped nor more rightful in making that determination than the parents themselves. Regarding the corruption brought on by undue wealth, I for one would trust my own children whom I have reared more than I trust governors who render no account in my mortality to me regarding the dispensing of my estate.