@BeAware when I was working for an agency doing only tourism websites I built their checkout and cart system completely new, from scratch, because it wasn’t accessible.
When I proposed the idea one guy asked:“Since when do disabled people book their holidays online?“ 
„Since the very second we start building a booking portal with them in mind and without thinking your way of ‚they don’t do that because they are incapable of it!“
Well. He quit later that year.