I wish I wasn't but what I am seeing lining up 21 months out are of either 1 of 2 possible scenarios playing out, where the GOP loses both:
(1) An unelectable DJT is nominated. I can see him being eaten alive by Mooch or some other faux centralist candidate.
(2) DeSantis or someone else gets the nomination, Trump feels slighted, and runs on a 3rd party ticket. This will pretty much be repeat of what happened in '92.
No argument there. I think those are the two most likely scenarios. I'm including under (2) a very late and/or backhanded Trump endorsement of the nominee.
To me, the best chance of avoiding that scenario is if the RNC gives Trump a prime time/keynote address at the RNC, where he gets his last big moment on stage in front of the entire convention, and chooses to give a rousing endorsement of the nominee.
I mean sure, it'll be all about him and everything he did, but as long as he ends it with something like "the best person to carry on for me is...", that's all that really matters.
I think that clearly would be the best move for Trump's own legacy and popularity within the party moving forward. The question is whether that will be enough to overcome his hurt feelings/disappointment/anger at not getting the nomination himself.
Obviously, the prerequisite for that is that the nomination is decided before the convention. If there's a nasty floor fight, then I think it very unlikely that Trump chooses to give an endorsement.
I still don't think that Biden ultimately is going to be the Democratic nominee. It's going to be somebody younger, and and much harder to beat than Joe Biden. So using "can they beat Biden" as the metric for determining which of the candidates are electable is dangerous