It's not because of a religious opposition to JS, but because usually Javascript-laden sites take a long time to load, require the latest hardware and browsers, and come with pop-up banners, third-party ads, and bloatware.
What we need is a distinction of “low JS”, which is really what we had before we somehow grew an industry of JS framework mania. JS with fallbacks is a very useful and pleasant thing, JS powering the entire experience is - in most cases - not.
A consequence of Rice's Theorem is that there can never be a useful, enforced distinction between the garbagepile that we have right now and anything more than "no JS".
Before WHATWG hijacked the web we had apps on the internet -- Flash, Java applets, etc. They had slightly more friction than ordinary webpages, which forced publishers to think hard about hey do I really need an app or can I do this with static HTML? Now maybe Flash and Java-applets aren't the best platforms for web apps, but the apps need to be kept separate from the documents, and there needs to be some small frictional cost imposed on publishers who choose the app route -- because otherwise all of them will choose it out of laziness.
