This feels like a really puritanical take on things. Fanned frets and multiscale absolutely help with the playability of an instrument. It’s physics, there’s nothing mystical or gimmicky about it.

Maybe YOU don’t want it, but it prevents strings from going flabby without needing much heavier gauges. Which does help with a wide range of playing styles and genres.

Unless you also believe that all guitars should have a single scale length or something, and a single neck profile and fingerboard radius. Otherwise if you concede that it comes down to feel+preference then there’s no argument to make against multiscale instruments.