I believe some of these improvements were part of the same work to eventually remove the GIL (global interpreter lock), albeit not tied to it. However, the final decision on removing the GIL hasn't been made.
https://lukasz.langa.pl/5d044f91-49c1-4170-aed1-62b6763e6ad0...
Edit: And to be fair, you can do "true" concurrency in Python you just have to eject to Multi-processing (with the tradeoffs that implies), so I didn't want to assume the comment was about GIL removal.