I find your version of history amusing, because the first project that I migrated away from vanilla JS was actually to Angular, because the team found React's JSX syntax too weird. And these weren't even the first wave of frameworks — people had been using state management systems long before then, but they had other flaws that made them difficult to work with in their own right. React became popular very quickly because it had a very simple rendering model, and because it was quick in comparison to a lot of other options at the time. Since then, the field has developed a lot, and at this point I wouldn't recommend React at all.
Out of curiosity, what would you recommend?
That said, it's kind of niche, which means you need to be more willing to write stuff yourself, so a good mainstream alternative is Vue. Vue is also signals-based and relatively lightweight, but still has a lot of batteries included and a wider ecosystem that is fairly strong. They're also great at taking the parts of other frameworks that work best and implementing them in Vue, but in a fairly considered way. I understand there's also some fairly battle-tested full-stack frameworks in the Vue ecosystem, although I've not had much personal experience of that.
Both libraries are signals-based, which is a completely different reactivity concept to React, which will take a bit of getting used to. But I suspect Vue will make that transition a bit easier - despite SolidJS's more superficial similarities to React, it behaves quite differently.