FWIW when it comes to Russia specifically, I would broadly agree that the problem there is not just the government but the culture as a whole (although we'd probably disagree about the specific things in that culture that are problematic). It is not obvious, though, and I think it always behooves one to be careful when making sweeping generalizations like that and carefully rationalize them.
You’re correct about Russia. And the same observation applies to the Indian subcontinent, where I’m from, as well. And, while you’re correct that each place requires a separate analysis, I would guess it applies to most places people leave.
People’s emotions and tribalism often make them romanticize the places they left. They attribute the good things about their society to the people and their culture, but externalize the bad things about their society. That’s usually self-deception.