There’s nothing wrong with voting your principles, win or lose.
It’s good to be honest, though, and say “I want Ted Cruz to be our nominee even though he can’t win, because he reflects my deeply held values”.
Well, no one should say “he can’t win”. At some point perhaps someone should be able to admit a likely outcome.
But not before there’s even been one vote cast. That to me is like a football team going on the road and saying, “We’re here to play but we’re going to get creamed!”
What would be the point of that?
Other than that I agree with what you’re basically saying.