This isn’t about losing a debate. I personally think he won the debate handily.
It’s about how he looked on the stage and his age and mental ability going forward. That’s going be forefront on the minds of many voters. If this was an isolated incident and he was just having a bad day, it’s a non issue for the Dems. Let’s all move along and this goes away.
The problem is that if things like this keep happening, it becomes an election losing situation. God forbid something worse than what we saw at the start of the debate happens in the Fall just a few months before election day. Trump would walk to an easy victory.
The reality is there are no other options that can beat Trump right now. Removing Biden can’t be an option unless there’s been much more going on behind the scenes in his day to day functioning than we don’t get to see. If there was any real thought (not silly media rumors) of actually replacing right now, it would lead me to believe that these things have been noticeable for quite some time and people close to him and the DNC have been trying to keep them from coming to light.