The leaders of the GOP know perfectly well that Trump is dangerous and irresponsible. They also know that the man on golf cart commands the loyalty of a majority of Republican voters, however, and they don’t have the nerve to cross him. As a result, they enable him, and pray that someone else will solve their problem for them.
The January 6 Committee is their deus ex machina. It is putting the blame squarely on Trump and his minions, not on the GOP as a whole. That’s perfect for the likes of McCarthy, McConnell, and DeSantis. They can rail about how unfair the process is, thereby maintaining their connection with the base, while the Democrats and the GOP dissidents destroy Trump’s reputation with swing voters, thereby making it more likely that someone else will be the nominee in 2024, which is exactly what they want.