I posted this in another thread and just deleted it because it probably fits better here. This is just a recent instance of him losing his train of thought and rambling aimlessly on stage. It's not hard to find a montage of him at his rallies not making sense. I mean this in all sincerity - it's sad what was happening to Joe Biden and it's sad that the same thing appears to be happening to Trump.
I don't believe Trump will step down and/or be replaced at the top of the GOP ticket though. I'm not really blaming anyone for that though.