They literally had the chance to stop him during his second impeachment after the attempted insurrection. Anyone who didn’t do it then, sure as hell isn’t going to do anything now.

The last thing the GOP wants to do is piss off his supporters right before the next presidential election. The electoral college could have ousted him during the 2016 election (as people had floated around) too. There’s just not enough people are willing or have the desire to reject him. Many would love to have him as a dictator, they just need the right pieces in the SCOTUS to say it’s in the constitution.

He’s 100% going to be the nominee now. Even if he goes to jail, he’s still going to be the nominee. The time for anything different is LONG past.