A power vacuum might make them implode on themselves.
“Might” being the operative word, and I don’t wanna roll those dice when line of succession is established. The cult only matters during the election. Handing the reins over to someone who shows no sign of breaking from the manipulators, but is much less likely to fuck it up by being a narcissistic geriatric idiot, seems unwise.
If you’re banking on disrupting the cult, the strategic time would be late in a (blatantly unconstitutional, yet inevitable) 2028 run. They already have the power now and, again, line of succession is predetermined. If Trump dies in office, there’s no clamoring for the presidency, it’s Vance. He’s no mastermind, but he’s not a doddering old fool. He’ll faithfully enact the will of his handlers without gaffes and senior moments.
If there’s gonna be a fascist puppet running the country, I’d rather it be a bumbling and incompetent one. At least he’ll screw up his orders from time to time.