I think he's showing more signs of dementia than anyone wants to admit, but my greatest concern is his lack of leadership. We need progressive voices making persuasive arguments and shouting down the narcissism and bigotry coming from moderates.
Biden is not that. He's spent more time in politics on the wrong side of history than the right one, and even at his best he has never been one to stand on principle and demand action. If he did wake up one day and decide to start fighting for future generations, he'd be laughably bad at it.
His memory, his wit, his gravitas, his voice, his authority, all of it is tied together, and all of it suffers with every gaffe or lapse.