Yes. Is that so weird? JS is also performant when you don’t use JS considering you’re running it on C or Rust and are likely using the FFI if you’re doing any form of computation heavy work.

Yes, it's very weird. When I write JavaScript, I expect it to run reasonably fast because of the JIT - and it does. I've never felt the need to use FFI, and libraries that use it generally do so because they want to interact with pre-existing C or C++ code, not because it's the only way to get decent performance.

Keep in mind performant just means that it works in an effective or expected way. It doesn’t necessarily say much about performance.

Yes. Python is performant when all the performance-sensitive code is written as extension code.