Pretty sure he's been showing visible signs of cognitive decline since 2020 elections. The sad part for people who aren't genocidal imperialists, is I'm not sure how much it matters either way. Supposing that he's not all there, a clear-minded Biden would likely be making much the same decisions, considering his past record in politics. So either way, he's still a piece of shit doing immense harm, whether he's all there mentally doing it or he's somewhat of a stand-in for it by this point.