This was discussed recently in another post and the answer I got was basically "until Google and Apple force us we have no obligation to change anything"
I suppose even then they won't be obligated to do anything at all... I guess there's no way for them to really notice how many people don't even go to the trouble of making their websites load... that's what I observe tech newbies do rather than switch browser from whatever I installed.
Yet we are increasingly seeing developers who won't follow those standards. What are we as developers going to do about that?