Ukraine is on the one hand a fairly small market, on the other hand a very corrupt totalitarian country, where a huge part of the "donations" will be bribery, money laundering, fraud, buying illegal goods.
So, probably, the company simply decided that it was easier to abandon this market rather than to solve the potential problems.
>moral principle because I didn't want to potentially help launder money to revolting dictatorships.
It is quite applicable to Ukraine as well.
People are literally being grabbed off the street and sent to die in storm troop units. Massive corruption, the main method of protection of which is that those who fight against it (or all their male relatives) are simply sent to die.
But I think it's more about the legal problems created by a small, toxic market than about high moral standards.
"It's a private service so they can do what they want" is missing the issue. Every private service in the jurisdiction is under the same legal constraints, so if the law is creating the incentive for them to screw their users, that is a problem with the law. Because then they all have the same incentive and converge on the same behavior and the usual defense to customer abuse by private companies -- switching to a competitor -- isn't available as a remedy.
This description sounds suspiciously similar to the situation in Russia for any male of fighting age or anyone who fights against corruption. I suppose a difference being that one country is forced to throw all its resources at stopping an invasion, and the other country is taking all its young men off the street simply to invade its neighbor.