No, we don’t have any plans on changing the stdlib to match PEP 8. As PEP 8 itself says, don’t break backward compatibility to comply with it. That leaves out public name changes. And we don’t accept changes for internal reformatting: it’s not worth the risk of breaking existing code, and it breaks pending PRs.
Additionally, reformatting existing code just for PEP 8 compliance takes up the already very limited (and almost entirely voluntary) resources for PR review that could be much better used for bug fixes and new features. Doing so would provide minimal practical benefit at a significant cost.
PEP 8 has a good use as a styling guide for incoming patches, but it’s most certainly not worthwhile to make the entire stdlib compliant.
Maybe you can treat it as a teaching opportunity to introduce some core Python values? Like “Readability counts” (isn’t it great that we have good code formatting guidelines and editors that help us implement them?), “Learn by doing” (our understanding and tools for making readable code have evolved a lot over the past 30 years), and “Practicality beats purity” (readability is important, but we shouldn’t be dogmatic about it, and should weigh it against other things like the risk of disruption from modifying old well-tested code).
I have also submitted an issue request to GitLab and a developer support request to GitHub that references the GitLab issue.
If CPython starts using it, maybe GitHub would be more likely to support it!
Please upvote/comment on this issue for GitLab and tell GitHub you want this.
If some code is being touched for other reasons (adding features, fixing a bug), then we might accept some reflowing, renaming of local variables and private methods, etc., as long as they actually improve the code. We can’t change publicly visible details, like visible function, method, and parameter names.
And we don’t want to accept general “cleanup” PRs because they’re hard to validate and might introduce breakages, just for the sake of looking better.
In the large, I’d say the answer to your question is that the stdlib is largely going to remain untouchable for code cleanups.