Nah, I'm with
@Euroamerican on that one. He did make enough public appearances for us to really observe his decline, step-by-step. Biden in 2020 wasn't even remotely close to how he is now. Yeah, he was old in 2020, but he was coherent. He didn't slur his speech, he didn't walk like a zombie, his face wasn't frozen in place as if someone had injected him with a metric ton of botox.
And as far as all that talk about "cocktails" goes, isn't that par for the course in that office? Kennedy was hooked on pills, Nixon and Johnson drank like desperate housewives; and former aides of Trump have attested that he pops adderalls like they're M&M's.