I've used plain react for a few things in the past few years. I strongly prefer it to next/nuxt/all this other stuff. Preact and an understanding of best practices can make it fairly performant with a more or less drop-in replacement if you're willing to sacrifice compatibility with absolutely all the ecosystem.
I still prefer svelte but it's less mature and universally-known. React is still a pretty good choice if you need something that will more or less work and that anyone can write.
My issue is opposite.
I know svelte/sveltekit and would want to contribute to svelte apps (a good reminder that I should)
But there are some projects that I really really want to contribute to / heck even port to sveltekit like cinny and hedgedoc and the likes and so I almost feel pressured by the system to learn react so that I can finally feel confident enough to understand their repositories as they scare me right now...
Cinny:https://github.com/cinnyapp/cinny Hedgedoc:https://github.com/hedgedoc/hedgedoc