Wrong question, IMO. I would vote for a rabid syphilitic badger before I voted for the Felon. But the Reps could have put someone up who, while I probably wouldn't like him, I wouldn't have been concerned about his/her competence.

They did. I mean, it's been a while, but remember that there were a bunch of folks who were running against Trump in the 2016 nominating contests. Trump won not because all the Republicans wanted him - he won because he had a solid 35% of the GOP, while you had a bunch of other candidates that split the remainder of the vote. At all times until the race was pretty much over, the Cruz-Rubio-Kasich triumvirate drew significantly more support than Trump.

Once he won the nomination, there was no way the party was going to just not support him - just like the Democrats wouldn't have conceded the 2024 election if Biden had decided not to abandon his race.

This specific criticism of Republicans is that the ones who still support him must be delusional or lying to themselves if they continue to support Trump while he is President. Which is wrong, I think. The ones who still support him are the ones who place a lot of importance on the things where they like his policies (immigration, social conservative issues, undoing globalization, and being a fighter against progressives) and they don't give much of a patoot about other things (the Kennedy Center, personal-enriching side deals, destabilizing global alliances, etc.). That's not self-delusion or lying to themselves, it's just not caring about the same things to the same degree as his critics.