PyPy isn't unmaintained. We are certainly fixing bugs and are occasionally improving the jit. However, the remaining core devs (me among them) don't have the capacity to keep up with cpython. So for supporting new cpython versions we'll need new people to step up. For 3.12 this has started, we have a new contributor who is pushing this along.
CPython has turned into a commercial enterprise where a small number of developers chase away everyone and periodically get useless projects funded by corporations that go nowhere after five years. Intelligent people have all left.
The 150th rewrite of unicodeobject.c is relatively benign (except that it probably costs RedHat money) but the other things are impossible to keep up with.
The text merged to the documentation is more concise than the PR title:
> not actively developed anymore