Yes, all of which, to me, look either like uncharitable interpretations or just straight up lies to try to make him seem more infirm. I stand by not seeing any sign of true mental decline, he seems about as sharp as an 81 year old can be. It's just that "as an 81 year old can be" is going to be a level well below what many people want to see in their leader. To wit, I think, personally, that Biden is probably mentally adroit enough to serve and continue to serve as president. However, it is very clear that most Americans don't think so, and at the end of the day, that's the dagger.
It probably hurts Biden that most people see his age and think "well that's disqualifying" but see Trump's mindless, actual cheese-slipping-off-the-cracker nonsense and think it's fine because he says it with a strong voice and not the softer sounds of an older man.
Frankly, I think if Biden had the forcefulness of his voice that Trump does, he'd be fine right now, even with the debate misstep. But it is what it is, if his numbers don't rebound over the next week, I think he'll get pushed to exit from all quarters.