Both candidates are experiencing decline, and if Biden were elected and incapable of doing the job it would have resulted in a Harris Presidency anyway. It's such an odd thing to object over. We've had presidents in decline before and the country kept running just fine, (FDR, Reagan.)
Biden did a fine job in office, I'm especially proud of his union support, and his policies were spot on in my opinion. To throw him under the bus like this seems really shitty.