The GIL only gets in the way of parallelism. Yes there is real hatred. You can experience it if you visit #python on libera and ask anything about threads. "Aieee! The non-determinism! The race conditions! Etc." Of course the async requires an async version of the whole i/o system, it can block on long computations or the wrong system calls, etc. And many rock solid systems are written in Erlang, which uses preemptive lightweight processes for all its concurrency needs.

Lots of microcontroller OS's use cooperative multitasking but once there are enough machine resource's, OS's generally become preemptive. Async concurrency is basically cooperative multitasking with similar issues. Does Python give a way to open a file asynchronously in Linux? It's now possible with io_uring but it was impossible for a very long time (like decades). Erlang and GHC both use thread pools to deal with that. The use the old synchronous open(2) call but move it into an auxiliary thread so it won't block the calling thread.