You’re leaving a few important bits out.
- Ukraine is a sovereign, democratic nation whose own citizens get to decide their future (not “ the west” or Vladimir Putin)
- Putin can’t withstand any of the current sanctions for long (and that’s not even factoring in things that the US is about to do to him)
- Any looming military takeover of Ukraine will be met with a bloody and protracted insurgency, which would be funded by highly sophisticated weapons from the outside, and executed by a population with a warrior mentality and an intense desire to succeed - in stark contrast to Russian soldiers who have little interest in being there In the first place.
So instead of capitulating to Vladimir Putin by rewarding his invasion with concessions he wanted before he invaded, a likelier scenario is he will eventually gain control of larger cities, attempt to emplace a puppet leader, fight a violent insurgency, with sanctions that will annihilate him from within, to where he will quickly realize that whatever gains he made in Ukraine will be meaningless if he can’t hold onto power in Russia.