But… Russia isn't the only place causing oligarchs to have quote marks around the word "accident", it's simply a state that's bad at the coverup.
I don't know at what point his private jet suffers a mysterious decompression, or his drugs are tainted with a lethal agent, or whatever, and it's possible his conversations with Russia have included such threats already. But eventually, playing with all this fire, worldwide, burns are inevitable.
There's a reason former US presidents get secret service protection for life, and they're term-limited.
This would all still be the case even if he was just making the kind of waves most of the west likes, rather than… not even just this, also encouraging a civil war in a nuclear armed state.
I’m in favour of consequences but that’s fairness bias at work, he’s gotten away with so much for so long, its likely it will keep happening and he will live a long life in absolute luxury.