Since Russia has recently announced they're withdrawing a part of
their troops and most of the non-Kurdish regions are now under Assad's
control, it's clear that the 7 year war is coming to an end with a
clear victory by the ruling government party.
This statement overstates the extent to which the Syrian Civil War is over, or nearly over.
There are significant parts of Syria that are firmly under Assad's control. There are significant parts of Syria that are not under Assad's control. Assad asserts the right to control the entire country and is deploying his domestic military resources to do so. See this map (I can't figure out how to get a current version of it to post in this answer.) Eyeballing it, Assad's regime controls maybe half of the inhabitable territory of the country (some of the territory is a no man's land of uninhabitable desert).
One of the non-Assad factions in Syria, ISIS, is pretty much defeated. But, most of that territory was controlled by Kurdish factions and there are also non-Kurdish factions that control significant territory in Syria (while these areas look small on a map, the non-Kurdish rebel areas have high population density relative to much of the rest of the country).
Also, while Assad is recognized by Russia and some countries as the legitimate government of Syria, his regime does not have universal international recognition of its legitimacy by any means. You can't deport refugees to a regime that you don't recognize as legitimate and don't have diplomatic relations with, which is the case of the EU nations vis-a-vis Assad's regime.
There is an ongoing and active civil war in Syria that will not end until there is either a formal diplomatic partition of Syria between the factions that currently control territory there, or Assad (or some other faction) uses military power to control the entire country. Neither outcome is imminent. Until that happens, we are merely in a lull in the fighting, and no part of Syria can be considered truly "peaceful" in even the medium term of one to a few years.
As a historical comparison, the Taliban was a lot closer to controlling all of Afghanistan than Assad is in the case of Syria, when a U.S. intervention following 9-11 led to the complete removal of the Taliban from power and the establishment of a new regime that drew heavily on the warlords who were on their last legs fighting the Taliban when the U.S. intervened. But, a decade and a half later, Afghanistan is still not at peace, with the Taliban now playing the part of rebels. Indeed, Afghanistan is now still second only to Syria as a source of European refugees.
Thus, even if Assad gained nominal control over all of Syria's territory, an insurgency could persist for a decade or more, without a resolution in the form of a treaty or something similar.
This state of ongoing civil war makes it effectively impossible to repatriate refugees to Syria. Moreover, some asylum seekers would face persecution upon return no matter which faction ends up winning, because those particular asylum seekers are too strongly associated with whoever the eventual losers in the civil war will be. So, only a portion (not yet discernible) of the refugees will ever be eligible for return.