mind sharing a link or two on the native code generation bit? I'm far behind from the scene but still curious.

They probably mean that modern RN apps can now use a lot of native widgets. You can look at https://docs.expo.dev/versions/latest/sdk/ui/universal/

There's also a project to add a static JS compiler, but it's been in development hell for the last 3 years: https://github.com/facebook/hermes/tree/static_h