devs probably not (ie: as NoSql, Kubernetes and stuff, some people pick overkill things, and by some I also mean me!), but React/Vue as libraries, certainly!

A SPA is a niche among the most mainstream web site. It makes sense when the interactivity is BIGLY on the cliente (like for example: A paint app).

But most things on web are not 90% client vs 10% server. Is the opposite.

Your todos, mail client, eCommerce site, blog, etc are better served with a server-side approach (note also how much important security is on this kind of apps!).

Your screen that display an interactive map, your game, paint app must certainly need a more client-first approach.

But as SPAs says: Is a "SINGLE" app. One.

Is your full app ONLY ONE? No? Then you are not in the niche, and if you actually have that SINGLE screen/app is likely a fraction of the whole thing.

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Another possibility is that single thing consume so much that you say, screw it, lets do the rest similar even if is a poor-fit, but I think that is rarely if ever the best (for the users!). This is what drive adoption, React/Vue solve nicely some hard stuff and naively you think is great for the most basic one. But as show the fact that stuff like "back button" get broken without EXTRA workarounds is not the best fit for them...

P.D: Is my opinion -after try for years do the opposite!- that the majority of the web apps be server-driven and maybe add a little of react/vue/alpine for extra nice touch...