I mean, I get what Zelen is saying about immigration, there he made no departure. But I feel as proven by Biden following through on Trump's Afghanistan plans to disastrous effect, we never should've embraced dove policies if we intend to keep America First relevant within the international political landscape. We need to stay a superpower and part of that is funding our military and applying pressure, whether political, economic or sometimes even otherwise, where necessary to threats. We also kinda abandoned our allies abroad and weakened most of our political alliances that had been built up over decades, which I personally felt was less conservative and more just questionable.
Likewise, I'm all for fair trade over free trade (I wish he had tried to break apart the WTO), but it definitely departed from the Republican mainstream as I perceived it since Reagan.
Also fiscally there was a huge departure. Man doubled our deficit in an up economy/market.
Even culturally, he was friendly to the LGB (but not T) community, and while I'm not gonna fault him for that, the guy wasn't super culturally conservative as proven by his own lifestyle. Definitely not a strong Christian, or fighting for that kinda thing, which used to be pretty strongly linked to conservative principles, though I'm not really gonna complain about changing demographics there.
So I think he did depart from core Republican principles as they stood when he seized the party and changed its meaning. I'm not gonna complain about many of those changes, but calling the people who refused to change their ideology RINOs just doesn't make much sense to me.