It takes years to plan a presidential run and the incumbent has a huge advantage. It’s infeasible to change the candidate now and would 100% split an already very polarized party. It’s a fake media controversy and the media companies are the ones causing people to feel that way by editing footage to make Biden look bad, attacking Biden’s stutter or slip up instead of Trump’s lies and gaslighting. The media is controlled by the rich and complicit in treason, but the rich never get their dues and the right is never held accountable.