Is not Trump running for President as "revenge" because the "humiliation" he suffered last time?
It may also have something to do with the multiple investigations he is under, in his mind, if he manages to become president again, he could try to use this power to get rid of the possible legal problems he could encounter after he finishes his second term, since I doubt he would get indicted as sitting president.
That is just speculation, of course.
It is quite weird. He lost the elections in 2020 and then created all sort of drama about it. Now even if decided to run for 2024, and wins the GOP nomination, a lot of voters will remember what he did in 2020 and that will have an impact on their voting patterns. Trump is extremely selfish. After he lost in 2020 POTUS election, he refused to campaign for the Republican candidate for the Georgia senate runoffs. And even during the recent midterms, he pushed a lot of unelectable candidates, which eventually gave Democrats the control of senate.
My take is - Trump is able to attract sizable number of votes (and at the same time lose almost an equal number of votes), but in the long term he is detrimental to the long term prospects of the Republican Party. He only cares about himself and will go against the party if he doesn't get what he need. This guy has transformed the GOP from a center-right political party to one at the fringe of the political spectrum.