I guess most the 400.000 - 800.000 Euromaidan protestors were CIA agents in Russias view then?
No, obviously, in the same way it would be ridiculous to claim that every single person who supports separatism is a secret agent for Russia. The claim in both cases is that the movement received foreign support, allowing it to convince more ordinary people to support it than they would have otherwise.
It’s well known that many people in Eastern European countries don’t trust Russia one bit after their experiences in the USSR.
Russia is not the USSR. And most people experienced a decline in quality of life, across every objective metric, following its collapse.
It's also well known that many people in eastern Ukraine have ethnic, cultural, and family ties to Russia, so it wouldn't be surprising if a lot of them wanted to have more favorable relations with them. This goes back to when the Soviets transferred the territory to Ukraine in the first place.
Before the war, people weren’t really aware of the situation in Ukraine and there were 100 other problems that seemed more urgent
Yes, that's exactly what I'm saying. Americans don't actually care about Ukrainians, most people barely knew they existed and couldn't find the country on the map. The only reason people started caring is because they started being relevant to state interests.
Ultimately this has to be decided by the Ukrainian people.
No it won't. The Ukrainian people do not have the option to vote on whether or not to accept territorial concessions, because they don't have a democracy, and even what pretense of democracy they used to have has been suspended due to the war. The Ukrainian state may get to decide that, but that is not the same as the Ukrainian people. You don't seem to be separating the state's interests from the people's interests at all.