I think the point is not that there aren't alternatives—there were plenty of jQuery alternatives—but that React is the dominant force, and this too shall pass.
React won’t topple for a while, because of none of the alternatives are different enough. React solved a real problem many developers faced by giving them a state management system with a rendering engine, whereas you were likely to make surgical cuts before in response to state change, you can now just write your ui assuming the whole thing rerenders in response to changes to that state. The component system also allowed for an easy way of sharing code as dependencies. Vue, Svelte, Solid and the rest have their individual pros and cons when compared to react, but they are essentially different attempts to do the same thing.
You want to topple react, you need to solve a problem that’s as big as state management used to be in a way that react can’t also just copy/absorb, and you have to do it so well that developers will push to use it at work. You need to have a ux as clean as what React offers to its devs, and you probably need to come close enough in benchmarks to not get instantly shot down.
