MAGAts are mostly a protest movement against the Establishment. And they count both parties as the Establishment. The politicians such as Boebert attempting to cash in on this anger understand that.
In a funny way, it amounts to being a different sort of RINO. Back in the Tea Party days (how quaint that now seems), RINO meant someone too centrist, a Republican Lite if you will.
Now folks like the Freedom caucus, Boebert, and even trump are in effect saying "The Republicans are evil and must be stopped. We are running under their banner because to get elected you must be under one or the other banner. But our goal is to destroy everything the R party ever stood for and replace it with MAGAtism from shining white sea to shining white sea. We’re RINOs too, but from the extreme side, not the centrist side.
They don’t use those words, but IMO that’s the message. And a nice irony it is.