Polls and support in a country where the opposition is send to jail, there is a law that penalises with 15 years saying anything else than the "official truth" and, in general, has demolished systematically any dissenting voice means very little.
We tend to forget that one of the pillars of a Democracy is free press. The fact that a candidate is "elected" means nothing when the electorate is kept in the dark.
I agree with you. Putin destroyed free press and opposition. But even if don't beleive in polls, all things shows that majority of people support war in Ukraine. One reasons of it is that they see one truth on TV and media is washing their brain for few decades. They blame NATO and US for this war, or as @xandry said - pindos and geyropa. And these who don't support it, they keep silent because they simply fear to ruin lifes for themselves and their families.
I am not sure what you consider all things in this context, despite that, there is a difference between a democracy and a despotic regime. In a democracy, the people of a country are to blame for unethical behaviours of their countries, however in a Tzardom, at most they can be blamed for not revolting or being, mostly, apathic about it.