Except, like Trump, they get more stupid as you go.

Nope. Putin _is_ a mad dictator completely disconnected from the realities of Russia. Just like Maduro in Venezuela. So if he's killed, nobody is going to be bothered by this except a few dozen of his closest allies.

Putin's regime is purely authoritarian ("information autocracy") it has _no_ ideology. Moreover, the government in Russia does everything it can to keep the population passive.

And before you ask, Iran was different because it's _not_ an authoritarian country. It's a full-blown totalitarian theocracy with an official ideology and the elites there actually _believe_ in their doctrine. They have a core of people who will die rather than betray it. And most importantly, they have actual institutions that can survive the death of individuals.