That's the thing, people will wear an accessory, but different people will wear different accessories and will absolutely refuse to wear others.
It makes it very hard for a business when, for instance, very few men are willing to wear your bangle or people can't wear your glucose monitoring hat inside nice restaurants.
It's likely that different wearable forms will become more common and accepted, but that is one of those predictions you hear every year for the last thirty years and it's true to an extent but also there is a long way to go.
Doesn't seem like a big problem since enthusiasts and early adopters are precisely the type of folks who would most likely break established norms in using the product.
Maybe one day it will be common for men to wear bangles on each arm, or for hat wearing to be common indoors via their actions.
For example, no one carried around headphones out-and-about before the Walkman.
It just can't look too unusual.