There are other barriers to adoption besides network effects. I showed in another comment downthread how easy it is to inject React into just the parts of an otherwise static web page that need enhanced interactivity. Svelte and Qwik need to be compiled – if you don't already have a full modern frontend build chain, that's a huge added maintenance cost.

Solid, to their credit, does have some support for using it in non-compiled environments: https://github.com/solidjs/solid/tree/main/packages/solid/ht...