The bashing of jQuery comes from junior devs. Of course a VDOM is clearer, more productive (and less performant) however most webapps with a minimum of logic have many legitimate uses of native dom/jquery in addition to the VDOM. And the interaction is perfectly safe as long as you do native DOM in the right lifecycle method (mounted).
jQuery is a pleasure to use and give us a lot of power/expressivity.
More generally this vague of juniors devs (e.g. CSS-in-JS lobby) are becoming less and less familiar with the concept of CSS/DOM selectors, despite their awesomeness and uniformity both for DOM operations, styling operations and integration tests operations (cypress)
BTW a little known fact is that jQuery is not just sugar and cross-browser consistentcy, in fact it push the boundaries of what is possible vs native CSS, see e.g. the reverse direction paradigm shift of https://api.jquery.com/has-selector/
Although its true that augmenting jQuery with a batcher for performance doesn't seems currently possible?
https://github.com/wilsonpage/fastdom
Not sure you read the submission, but the move away from jQuery was not to move to anything "virtual DOM"/React/similar but rather that the functions provided by jQuery now have vanilla/"native" alternatives.
I do think that your complaint, while applicable to a lot of websites, is not specifically applicable to GOV.UK. They do everything to use plain HTML (and if possible no Javascript at all, but there are certain pages where Javascript is an absolute must like interactive maps), and they aren't using React but instead a special framework that is designed to minimise Javascript even to novice developers. Basically they've replaced jQuery with plain Javascript since that some older devices they're supporting (which jQuery is a better solution as it's bug-tested and optimised as much as possible) is dead.
The main value I found with jQuery was that the more your CSS selectors and jQuery selectors diverged, the more it felt like you were doing the same work twice.
Now I'm curious what the CSS looks like for devs who have only ever known VDOM frameworks. Regular CSS can be pretty bad, particularly on a mature project. Are we talking dumpster fire or three ring circus here?
When jQuery was in its prime, stubbornella was a fixture of youtube playlists. One of the feathers in her cap was cutting yahoo's CSS in half, which resonated with a lot of us. CSS has been problematic for a long time.
I used to hate code generators because the code quality was always so bad that if a midlevel or senior dev was writing code like that I'd be talking to our manager about firing them, and for a junior dev we'd be talking about more intensive mentoring or even a PIP.
Once Sass introduced SCSS, that was the first code generator I ever met that actually impressed me, and Less is very close. The default CSS out of it looked very much like the sort of CSS you would expect from a project after someone had already gone through and cleaned up all of the cliched failure modes for medium sized projects. It felt like having a fast forward button. Still one of the fastest 'sells' for me, and I do quite a lot of technology selection for projects.
Not that it's perfect. Poorly written mixins/functions can generate way more CSS per call than is necessary, and I have a team of overbooked people that I need to sell on prioritizing fixing this sort of thing and I just can't find the bandwidth because there are always 2 more pressing issues I need to talk to them about. I can't squeeze blood from stone, and I can only ask for personal favors about as frequently as I can grant them, modulo any turnover - which has become a problem. Turns out if I take a shine to you, you're also really easy to hire somewhere else.
