The way I would reframe this is "why do winners of the Iowa caucus tend to come up short?"
It seems to me that the committed social conservative candidates are just not good fits for the party at large. Most of the time culture warriors aren't able to wrangle control the way the establishment candidates tend to. That being said, there's always cases such as Trump. He didn't really portray himself as a social conservatives, but he was the culture warrior in 2016.
That being said, a reversion wouldn't surprise me, with the establishment (Pence/Haley/Rubio etc) comes out over the social conservative (Hawley/Cruz/Pompeo). Establishment candidates get picked by the establishment for a reason, and it's normally that they're the most broadly palpable choice.
it could also end up being a fusion of the two who wins the primary next time. Trump would probably fit in both categories. Oddly enough, Ben Sasse probably would too.
Another sign that we're finally, at long last, exiting the Reagan Era of moral panics. It couldn't have come soon enough.
