All the Putin jokes aside, I don't think he's doing it for geopolitical or treasonous reasons. I think it's mainly just a by-product of his style of interaction and competition, which exists for very logical ("logical") reasons and which he's been able to make work pretty well for himself.
https://snyder.substack.com/p/the-weak-strongman
Snyder says it better than I can, but basically, he is weak and stupid, but he needs to be able to dominate people around him, and so his whole strategy is to attack and weaken, because that's his only way to be able to compete effectively. He can usually dominate the weakened version of whatever he's attacking, in a way he never could if it was at full strength. It's why he shows such innate and passionate violence against anything or anyone that is organized, effective, or popular: Because someday, they might turn against him, and if they did they would definitely win, and so he has to Nancy Kerrigan them before they get a chance.
Again Snyder summarizes it better, but it is also the exact same model that Putin uses, and it's had exactly the same effect on Russia (taking it from at least a regional powerhouse and functioning country that could accomplish significant things, to being a pariah state that barely functions in the first place even internally.) The strategy only works for as long as there is no one "outside the wall" who can come into the sphere of influence in un-weakened form, and if that ever happens, then the strongman crumbles instantly into impotent rubble. To ever let one of these people get control of your country or organization is basically just a nonstop rolling catastrophe that just gets worse and worse the longer they hold on to power.
