This response is a bit dated but oh well. It was clear to me whatever drugs they usually give Biden to keep him more coherent were not given to him this time. So to me it was clear that they were ready to move on knowing how bad the polls have been for him. Of course they knew how bad mentally he was already but now they were given permission to say so out loud. Also think about the rule set for the debate. The mics were being cut off if your time runs out, who does this help? Well if you go back to 2020 the biggest criticism was that Trump was interrupting too much, a strategy I thought was unwise at the time because the best thing you can do to expose someone else is let them talk more, but I digress. As of today Biden has dropped out and will not seek the nomination and endorsed Harris (Who will not get the nomination in my opinion), so we will see what other swamp creature they prop up next.