> However, it's the site.py module that actually updates sys.prefix for the venv. So you may just be inspecting at the wrong point? Or possibly it's in a codepath that doesn't run on macOS because *previously* it was being set correctly in getpath instead of being deferred until later?

I just noticed the same. Is this intentional? This means that "python -S" doesn't work with a virtual environment. I also noticed that site.py's venv support contains some special code for framework builds that shouldn't be necessary. But I guess that's something for some other tickets.

I'm pretty sure I now just have to clean up my patch and create a PR from it.