The fact that there was some prior recognition is quite irrelevant. Should the EU nations claim their pre 1911 boundaries against the will of the people living there, by force?
Should the Lenape Native Americans whose predecessors sold Manhattan to the Dutch be able to reclaim it by force? How about the Dutch?
Your argument is sophistry, and nothing but inane justification for an authoritarian and expansionist regime.
Moreover while that regime repeatedly proclaims that no one should interfere in the internal affairs of other nations, it feels completely free to interfere and claim other nations, including, Tibet, Taiwan, and Hong Kong (yes it was leased and returned, but they are already violating the terms of the return).
This is not a regime to defend.