I don't see it that way but I do sympathise why others would.
I see this simply as one mans drive for a legacy.
He's accomplished most of his goals, becoming president, fabulously wealthy, absolute power in his country. When you have everything you still have to shoot for something more, for him it's to make Russia bigger and more complete. To be leader of a true superpower with all perceived wrongs righted.
This isn't about Russians, most Russian's don't give two hoots about Ukraine or wars. They've not been given a vote about it.
But in a way that's more scary for the west. It's not easy to negotiate with a power crazed maniac who has no respect for his own people, let along anyone elses. I know a couple of Russian people, they're very nice people and not pro-war. They just want to do a job, earn money, support their families.