It enables it for accessing from within Python, but doesn't enable Python itself to be installed into a long path. And because a venv is essentially an installation, they're included in that. (Possibly %PYTHONPATH% entries are too.)

I haven't checked how widely MAXPATHLEN is used, but it may be safe enough to just raise it. However, I think that's going to have a memory impact, because the paths used for initialization are kept around for the whole length of the application now. It might be okay though, not sure how many paths are kept.

I'm still keen to see the whole getpath implementation replaced with Python code (with suitably injected native helpers), which would make it much easier for us to use dynamically allocated strings of any length. The current implementation is a way off being able to handle this.