Surveys on the approval of Putin and the invasion of Ukraine in 2014 showed numbers between 80% - 90% of people approving the war.

I assume - one would need to check - that the majority of people who left Russia after 2022 did not support the war, so those left should be on the lower end.

"20% of Russians were ready to vote for an anti-war party in the last elections"

Yes, as I've said, approval dropped when Ukraine hit oil infra and gas prices went up, I can see 20% as a number. Nevertheless as show by approval ratings after 2014, that number was lower until people got hit by the impact of the war themselves.

Families of people who signed up for the war got large amounts of money. The transfer of money from the Russian national wealth fund into the economy, together with the shortage of workers, increased salaries.

[Edit] People didn't keep that money but spent it so others profited from that money too.

This is what happens in wars - beside war racketeers - salaries go up. There is a lot of research on how German profited from WW2 (and before) for example for most of the war. WW2 too seems most researched from what I see on how everyone profits until things get worse and end.

a "war chest" is usually saved by the state (by under-investing into everything civilian) and then given back to the working-class population as salaries, sign-up bonuses, investment into logistic infrastructure. If you look up the stats - there was a real-estate boom in the early years of the was as many families could finally take a mortgage. Now many cannot pay for it because the bonuses and soldier salaries "don't last" hence companies like "Samolyot" are now in trouble.

> If 99% of the Russian economy gets destroyed, he'd redirect the remaining 1% to fully fund the war.

This is impossible, even in a dictatorship.

Putin does not have absolute power entirely on his own (no dictator truly does). He can only continue with what he is doing because the Russian population on average either actively supports him or is not working against him.

If literally 99% of the Russian economy was destroyed, no matter how currently oppressed they presently are, the Russian people are likely to rise up and remove Putin. It'll be bloody as all hell but if the economy were to truly and completely collapse (let's say, all refineries were severely hit and taken out of commission for months), it would happen.