The problem with not using a JS framework is that eventually, the investors/business person/design team/frontend enjoying devs wants this highly animated site with all sorts of little toggles, confirmation boxes, popup models, toasts, etc.

It is far nicer doing that in React where you can just casually npm in some online component that does that rather than in vanilla JS or jQuery. React is basically a compromise between nice interactive websites and keeping it as programming.

Nothing stays simple and when it stops being simple, you want React.

Developers like simple sites like Hacker News. Nobody else does.