I feel like there's a reasonable chance that his administration offs him to give themselves a ton of political capital. His incompetence and narcissism have been major impediments to ushering in fascism. He's been tolerated because of the popular support he has been able to drum up, but that's all.
However, his popularity has been waning and it's only getting worse. His cognitive decline is becoming harder to hide from the base. Realistically, how much more use can they squeeze out of him? How long before they decide that he'd be worth more to the movement as a martyr than as a fading demagogue?
They could stage it as an assassination by the left and use it as a pretense to push an authoritarian takeover. Worse, they know Democrats would give them a huge amount of leeway to do it out of a misguided sense of "unity and healing." We've already seen how they react to assassination attempts - Democrats bent over backwards to appease Republicans so as not to appear divisive.
I'm positive that, at the very least, these conversations have been happening within far right circles.