Because the globalists fucked up by going with Kamala Harris as VP, so when Biden started to malfunction they didn't have an easy way to switch gears mid-stream since they don't want Harris anymore than the rest of us want her. So their best option at this point is let him be publicly embarrassed so the partisan hacks call for him to be replaced so they won't get mad at the convention when the DNC swaps him out with someone else.