What about Rails and Svelte? While many people are doing things with full stack Rails, there are just as many using Rails (whether as a monolith or separate backend from frontend deployments) with modern JS.

Actually, in recent Rails versions the mistakes of Webpacker have been replaced with much more flexible gems for building frontend assets with esbuild, vite, or any other build tool.

This gives the ability to seamlessly blend the nice pre packaged rails ecosystem with the nice ecosystem of react components or other modern frontend tooling most people are using.

I close this comment with mentioning: you still may not need all of that new stuff! What does your app actually do?