That opinion can only be from the Biden supporters who wanted him to show how competent he was mentally and physically.
But anyone with half a brain -- and not under any delusion -- could have seen that since January 6, 2020 this man was incapable of even an ordinary job -- let alone that of president of the USA. Barack Obama has been the actual "president" all along, and all the destructive policies of Biden are actually his.
It was Biden who challenged Trump, not vice versa: "President Joe Biden’s campaign has released a new video challenging former President Donald Trump to two presidential debates hosted by news organizations. The video comes as Biden has formally informed the Commission on Presidential Debates that he will not participate in its previously scheduled fall debates."
https://www.cnn.com/2024/05/15/poli...residential-debate-challenge-saenz-cnc-digvid
So he got his wish, and even refused to be drug tested (which is what Trump wanted). And now that the world has seen the total incompetence (and also the destructive agenda of Biden as laid out by Trump), the Leftists are wringing their hands. But in some states, they will not allow a switch out of candidates. Also none of the alternatives to Biden have any merit.
So they simply plan to steal this election in the end.