I am not sure what "web" you're using, but as someone who uses noscript and has been enabling scripts for over a year now, I can firmly say JS is NOT used for making "desktop-class applications more accessible".
It's used for ads. And spying. Lots and lots of spying.
Seriously.
Googletagmanager/analytics is everywhere, it doesn't deserve to be, it doesn't need to be. That domain needs to die a painful, horrible death.
facebook, twitter, sessioncam, and many others are used to bloat pages, increase my energy usage, decrease my battery quicker and contribute to the wastage of energy on an unprecedented scale.
Just ask yourself, how much money, battery life, bandwidth is spent every year on downloading useless scripts that as far as I can see offer no value whatsoever. By selectively deciding what scripts to enable I get the folliowing result:
1: pages are lighter, less bloated, and STILL WORK
2: I download less scripts, use less battery and save bandwidth and energy for myself and all humanity.
3: There is less spying as fetch() requests are blocked and there can be hundreds of them across a single web-page session (you can watch really bloated pages for 10 minutes, there can be 100's of requests easily).
Test: load the following two pages, study their usage, test each with JS enabled/disabled:
1: https://old.reddit.com (with JS:2.69, without: 2.34mb)
2: https://reddit.com (with JS: 8.58mb, without: 8.10kb, but the page is broken...)
Baring in mind old.reddit works fine with JS disabled, showing JS is not needed for a site like reddit to work at all.
Yet, "web developers" use them as if it's nothing. Pages that execute over seconds, possibly MB's of data, all the additional requests that are made to enrich the likes of FB/Google et al.
So no, SPA are a scam and the web is worse today than I remember back in the 2000's, at least we didn't have cookie pop up boxes because people can't help but abuse JS.
Most of the GDPR violations I've found thus far are from scripts that have no place or purpose, that slurp up user data without remorse, that, if disabled, doesn't impact the functionality of the page, and that enables the great surveillance capitalism and data-raping we are seeing today.