Cocaine ages the brain, which leads to dementia. If he was into it, it explains his decade long decline before our very eyes — it would have started his descent all those years ago. We've watched his increasing dementia since he descended that staircase in 2015. After he had covid, I would say it accelerated. Then, the trauma of that attempted assassination definitely accelerated his decent into dementia.
I agree that dementia on top of his lifelong narcissism and general moral turpitude makes him dangerous — and everyone still following enabling him make themselves into his weapon.