I notice that some people like to stab the keys. They seem to use an excessive amount of force. I've always been all about using the least effort possible so low-profile keyboards seemed optimal to me. You just need barely a touch to register a keystroke. Mechanical keyboards seem built for excessive travel time in comparison.
I have no evidence of this but I really do wonder if excessive typing force contributes to RSI/CTS.
The author here really did go down a rabbit hole and I suggest that as soon as you look at changing layouts, you've perhaps gone a bit too far. At some point you'll be using a keyboard that isn't yours. The universality of QWERTY (or whatever the equivalent is in your locale) has virtues all of its own.
My only real objection to mechanical keyboards is people who use super-clacky keyboards in an open-plan environment. That's just antisocial and inconsiderate.