I should have been more clear - my point is not so much that people should use vanilla JS rather than a framework, it’s more that the majority of SPAs I’m force

I should have been more clear - my point is not so much that people should use vanilla JS rather than a framework, it’s more that the majority of SPAs I’m forced to interact with could have been implemented just as well with HTML, CSS, and a relatively small amount of JavaScript - small enough to not beg for any kind of framework at all. If the nature of the app really truly demands a full-blown SPA, then by all means go all in on something like React.