The claim might be true among YC companies or even startups... but the majority of websites by far don't use React/Vue: https://w3techs.com/technologies/history_overview/javascript...

I'm not saying that React/Vue aren't important and drastically changing what's thought of as best-practices in web development... but just because everyone on HN uses a front-end framework for their websites doesn't mean "all websites" do it.