You have to program it using Ruby which is not a good language. It's slow. It doesn't have good static type annotations (as far as I can tell the community "gets it" even less than in Python).

Rails also uses way too much magic to dynamically construct identifiers and do control flow.

The over-use of magic and the under-use of static types makes it extraordinarily difficult to navigate Rails codebases. It's one of those things where you have to understand the entire codebase to be able to find anything. Tractable for tiny projects. For large projects it's a disaster.

Rails is a bad choice (as is Ruby).

My favourite web framework at the moment is Deno's Fresh. You get the pleasure of TSX but it's based around easy SSR rather than complex state management and hooks. Plus because it's Deno it's trivial to set up.