React is great when you absolutely need state management on the frontend, but is overkill for the vast majority of frontend components to the point I would say it basically doubles the time to create a SPA. I wish I could just import it for one-off components and use traditional HTML rendered by the server for everything else.
We can also use React for that–the issue is the bundle size and it does not appear to be designed to share the DOM. I would love to see these smaller libraries document the process and best practices for using them within otherwise vanilla environments.