Actually, he’s right
Winning the nomination and winning a general election are two separate tasks.
The Democrats have used the term “MAGA Republican” with modest success. The reason Reagan won was his appeal to independent voters in both 1980 and especially in 1984 along with a united conservative base
MAGA, though passionate, do not represent the majority of the country. In fact, I would say they are out numbered by the left.
It appears that whoever gets the Republican nomination in 2024, is going to do so, with a fractured party. To overcome the advantages the Democrats have, both by default and things they put in place for themselves to give them an advantage, the republican nominee has to not only secure the Republican base, but attract enough swing voters, especially in suburban areas to win the WH