Well, yes and no.
The two political parties are not membership, representative organizations, they do not exist in the Constitution, and they are more or less free to run their affairs as they choose.
We are still, on paper, a representative republic. We could, in theory, still have Legislatures and a Congress with zero Democrats and zero Republicans.
My tagline used to be "America will never be free until D+R are <218 in the House and <50 in the Senate".
So, whether or not you are a "registered" Republican or Democrat, you have no Constitutional or statutory right to be represented in the choice of a Presidential nominee. The value of your party membership is, as my grandma used to say, "That and a nickel will get you on the subway".
That being the case - if you think the GOP is going to conduct its affairs from today through July 2024 in a manner that allows ANY POSSIBILITY of Donald Trump being their nominee - you are out of your mind.
None of the Above?