Question: do you think the bureaucracy, the army and the FSB are going to be happy at that?

The army has been gutted by the war and is relying on mobiks. Even the hard core nationalists on TV are clearly showing signs of despair. Look how many Russian bodies are being thrown at Ukrainian lines to take tiny bits of land. At this rate, the whole Russian military will be ground to dust before it can even take the remainder of the Donbas.

YOU won't accept a Russian capitulation easily from the comfort of your room, but would the russian nationalists try to murder Putin, when he controls the whole murder regime? No, it is much, much more likely that the nationalists who threw a fit over any retreat would find themselves falling of of balconies before Putin would.

The oligarchs don't have any power anymore. That's one of the good things Putin did. The security forces are in charge.

I don't believe that at all. If it were true, Putin would have ordered a full mobilization already. It's his only chance of winning the war, and he still can't do it because the oligarchs would all flee like rats off a sinking ship if he tried, and the economy would collapse.