This is akin to asking if someone can tell an German name from a French name. Sure, there are some shared ones, but for most intents and purposes locals can easily tell the two apart.
Russia really isn't that similar to the rest of the Eastern Bloc. Even in language, the other Slavic languages are pretty close to one another, whereas Russian is pretty different. Same for culture etc. Russia is trying very hard to create the impression, that it's all the same, in the hopes of eventually occupying neighbors again, but it really isn't.
Russian is a Slavic language and very similar to other Slavic languages especially Ukrainian and Belarusian. Far closer than German and French. I have family across 5 different Slavic countries and hear various Slavic languages regularly. You're just spewing complete bs for political reasons apparently.
I speak most of the languages you listed on a conversational level, but sure, it's easier to cry about astroturfing than consider that you might be wrong.
