There are plenty of guitar innovations that should be standard by now but tradition won't let it happen. Composite fretboards, stainless steel frets, strap locks, LSR or graphite nuts, locking tuners...no reason for them not to be on most guitar.
I agree these are all great innovations but they all have some drawback and they don't make what preceded them 100% obsolete. Except maybe synthetic nuts. I see no downside there other than if it costs more thank cheap plastic or animal bone. Some players prefer a wood fretboard feel or nickel silver frets. An automatic transmission is a huge improvement over manual, but manual is still made and sells in small numbers. People still by vinyl instead of CD's or digital. Whether that's preference or tradition, dunno.