I understand the sentiment of running independent because the GOP establishment for the most part might as well be democrats. But, it’s one of the few scenarios (outside obvious cheating) that the democrats can win the presidency in 2024.
If Trump does run in 2024 he needs to remain in the GOP, otherwise Trump and the GOP candidate will split votes on the right/middle while the democrat nominee wins the election.
The republicans are despised and the democrats are despised. The economy will be historically bad. Trump can denounce The GOP on many policies and attract independents and democrats. He can say that he works best with republicans but he has decided that this move is necessary.