Because they don't really support it and don't really believe in it. And they aren't interested in being correct either. Back then it was a time for [some] of their families when they had a possibility to steal from and oppress people with their comfortable ass never being punished and they just want it back or someone (fsb) is feeding them promises about such life (which will never happen anyway) while using them as ~~puppets~~ cum socks for prolongement of such a world state, in which fsb's comfortable ass stays in power, tortures innocents and not receives enough what they really deserved (Ukrainian text on post's picture describes very well what exactly they deserved — death for everyone (especially chekists) standing on our way to liberation). Most definitely mentioned "someone" was just another fsb kremlinbot — i highly recommend to ignore them and if possible ban them straightforward or reply with real arguments (not for the sake of replying to bots since it's pointless and they aren't designed to ever be sane, moral and humane, but to show real people that there's still sanity in others) and beforehand... prepare yourself good not to fall in their psyop traps such as framing or personal assaults, whataboutism, switching roles (such as "we are victims", "we are denazificators", "we aren't occupative, we just want peace and we are right", "they started first", "our atrocities? look at this sloppy pic of poor ruzzian children being crucified by reptilians — and this certainly happened", "there are no millions of corpses buried in secret mass graves of red terror", "yes, you are in fact correct — it's all wrong and must end. exactly. yeah. we must win at all costs — even by killing our own families and friends" etc.). imo, people who are interested in how to protect oneself from psyops and soft endocrination of radical ideas will just go and search themselves for further info.

They are using same core techniques and their purpose is more to piece everyone off and shit as much as possible to make certain places on the internet unattractive and unusable for an adequate individuals, but they are designed to look differently and have different "opinions", idk whether lemmy's functionality lets them appearing as groups and even reply to each other to make an illusive "conversations" in the comments, but on some platforms it's also the case for quite a long while.

Also, another type of the same shit kremlinbots is so-called cuntbots, which just spam porn everywhere. However, their main purpose is the same.