One thing AE provides but not coroutines is type safety. More concretely AE can specify what a function can do and cannot do lexically in code. A generator/coroutine cannot.

For example, a function annotated with say `query_db(): User can Datebase` means the function can call database and the caller must provide a `Database` handler to call the `query_db`.

The constraint of what can do and not is pretty popular in other programming fields, most notably, NextJS. A server component CANNOT use client feature and a client component CANNOt access server db.