1. The tools available in vanilla have improved a lot recently and 2. LLMs have made niche skills/knowledge more accessible. SPAs still have their place but the average CRUD app is now really well served by vanilla or lightweight libraries like HTMX.
CSS was always pretty accessible. You just had to actually care to learn it.
On the other hand, the average CRUD app doesn’t care about the traffic and rendering overhead of a reactivity library such as Vue. Looking at the boilerplate code needed for basic reactivity that your sibling comment linked to in the Mozilla docs… no, thanks. Just eat the 16kb and have some decent ergonomics.