Sounds like a case of being in the right is not enough. The law in theory prevents this kind of stuff, but it might not have done enough of a job here.
Since my wife is Russian and we have lots of Russian friends we're not blind to these checks, but in all cases they were resolved by submitting residence documents. Success rate was 100%.
Of folks that were not residents however or that did not manage to prove their residence, very few got their accounts re-instantiated. We also had a case of someone who was not able to keep their account until they stopped receiving a Russian salary.
Based on my network of ex-colleagues who are now scattered all across Europe the best banking experience for foreigners is in Netherlands and the worst is in France, Spain and Poland. Germany is somewhere in the middle, for other countries I don't have datapoints.
The best part about Europe is the common market that includes online banking. Revolut and Bunq seem to accept all legal residents and that's enough for 90% of basic services. Life would be much harder without them.
Austria, but we both made personal and indirect experiences through friends all over the place. For instance my wife has accounts also in the UK and Estonia (guess why) and it was all pretty much the same thing. I have no experience in the Netherlands but friends moved to Poland and Spain (among other countries) and it all was absolutely fine.
The only people that ran into issues had monetary transfers in and out of Russia or folks who did not manage to actually immigrate properly. With regards to monetary transfers in and out of Russia, I even have that as an Austrian citizen, that to me is largely an unrelated problem to citizenship.
Since my wife is Russian and we have lots of Russian friends we're not blind to these checks, but in all cases they were resolved by submitting residence documents. Success rate was 100%.
Of folks that were not residents however or that did not manage to prove their residence, very few got their accounts re-instantiated. We also had a case of someone who was not able to keep their account until they stopped receiving a Russian salary.