An intelligent or competent leader probably wouldn’t be in power in a situation like this. This is a situation that arises when the partisans have chosen blind allegiance to a cult of personality over the kind of messy politics you get when you have to try to win the allegiance of a party by proposing policy that a majority can get behind.
Actually, no. They haven't "ceded" a damn thing. If they did, the GOP would be working on Trump's legislative agenda, which is something it's been sabotaging again and again in spite of having a slim majority in both the House and the Senate. The plan seems to be: sabotage until midterms, then lose one or both majorities to dems, and raise money off "gracefully losing" for the remaining 2 years of Trump's term. That was the plan 8 years ago, too. It worked.
An intelligent or competent leader who had the power currently enjoyed by the President would be able to implement the system suggested by Buffet, and it would likely see less opposition than the current tariffs have.