'#TrueScotsman' isn't just a fallacy. - it's an illustration of how power works: If you have power, you get to say who's "true"; if you don't your assessment doesn't matter.
E.g. 2 #FederalistSociety stalwarts have argued that Trump may be legally barred from holding office, which as the child of Goldwater Conservatives seems like it makes them credibly conservative. But if the #ConservativeMovement doesn't regard them as #TrueConservatives, their args will be ignored by #MovementConservatives.