Russia is a Mongol horde. Suing for peace against tribal border raiders (cooperate) is a rational strategy. If they know you'll always cooperate, then their best strategy is to always come back and attack (defect). Each time you achieve peace you lose land.
So, rational strategies are bad. You want to adopt an irrational strategy where you appear to be a crazy person willing to hurt themselves to get revenge - now attackers won't risk themselves in the first place.
This is why societies develop an "honor culture" and why NATO has that mutual defense clause.
In real life Putin changed strategies in a way that made his country worse (turned into a Mongol horde) but personally improved him (gave him more power over the country).
It seems his push for peace is always one sided in that all his ridiculous plans end with Russia being rewarded for aggression and Ukraine losing territory.
He said the people in those regions should be able to decide which country they want to be part of and that the result should be enforced/respected by both sides.
It’s a stupid opinion, but he didn’t say what you said he did.
Framing that as enemy propaganda is propaganda that you have fallen for.
Then a few weeks later regime approved voices said we should consider peace and it was no longer considered propaganda.