A good number of those amendments (about 25% of them) to the Irish constitution were over international treaties (as seen on the Wikipedia list), ranging from the various EU treaties (Ireland pretty much had an amendment/referendum for every one of those: accession, SEA, Nice, Lisbon, Amsterdam, the Fiscal Compact) to participation in the ICC and the Good Friday Agreement. (The line was apparently drawn at an IMF bailout, which was judged not to require such a popular consultation, only the Dail voted on it.) Why is the US/UK solution better where only the Senate/Parliament approves international treaties?
And why is it bad that Ireland had multiple amendments/referenda on abortion (refining the issue) rather than let a (supreme) court superlegislate the matter (US)?
You could argue that the Irish constitution was bit too detailed/prescriptive in some of regards, e.g. including judges' pay or divorce minutiae, which may have been better relegated to statutes. But that doesn't seem to be a general problem with other rights which are only broadly outlined in the Irish constitution and the courts seem to have broad review powers. Some analyses have said that the Irish constitution is itself a mix of US, UK and continental European constitutional elements (French 1848; German Weimar). The more detailed/prescriptive bits seem to be in the vein of this last tradition. According another analysis, it was mostly the Catholic-inspired elements that were too detailed in the initial issue and this was actually a similarity with the Polish constitution of the time. So, perhaps in this view, amendments involving popular consultation but not being overwhelmingly difficult to achieve was perhaps a good thing in retrospect.
For more on what a prescriptive [vs procedural] constitution entails, see "Two constitutional archetypes" in this IDEA constitutional primer. Basically, the former is much more value-oriented and more typically adopted by nation-states as opposed to citizen-states; the latter/procedural kind contains "few[er] substantive provisions (provisions settling particular policy issues)". There is little doubt that the Irish constitution had substantial prescriptive elements in this sense:
In Ireland, too, the Irish Constitution of 1937 explicitly places the family and Catholicism at the
center of its constitutional identity, a fact that has been reaffirmed by the Irish Supreme Court.
So, at least part of those amendments are in this view an example of
a polity determined to
accommodate significant social change [that] seeks to do so under the restraining sway of [a] prescriptive
constitution.