I’ll add GvR own words at async-sig mailing list (italics are mine):
“I would caution against rushing into anything rash here. Nathaniel’s post
will stand as one of the most influential posts (about async I/O in Python)
of this generation, and curio is a beacon of clarity compared to asyncio.
However, asyncio has a much bigger responsibility at this point, as it’s in
the stdlib, and it must continue to support its existing APIs, on all
supported platforms, whether we like them or not.
I would love to see a design for a new API that focuses more on coroutines.
But it should be a new PEP aimed at Python 3.7 or 3.8.
I am tempted to start defending asyncio, but I’ll resist, because nothing
good can come from that."
Nathaniel’s post is: https://vorpus.org/blog/some-thoughts-on-asynchronous-api-design-in-a-post-asyncawait-world/