There are few things less accessible than web applications depending on bleeding edge javascript that might not get successfully executed. There are few things more accessible than text in an HTML web page on an HTML web site. If we really cared about accessibility for the differently abled we wouldn't be making such locked down, proprietary websites. But of course it's not really "we" doing this of our free will. It's corporations and their profit motives telling their human parts to make bad websites. And since that's where the money is in web dev it's become the default for all web devs and even shows up in institutional/government websites.
I don't think corps are going to change and I don't think something other than websites is the answer like the author suggests. We just need actual websites with web pages with text.