I'd mostly agree. SPAs can do things hard to do with URLs and form inputs; for instance, chess would be harder to program in the browser without JS (though I remember an opening explorer which worked that way). Or if you think about popping up a modal or a toast. But a lot of the functionality is duplicated.

This gets even more extreme now that you can have wasm on a canvas... The language that you're compiling from doesn't understand the semantics of a back button either!