There are plenty of other ways to get a venv through a potentially unexpected path (turns out I've been doing one for years), which is why I went with the general warning rather than limiting it to specific behaviours that are subject to change outside of our control.

I'm not opposed to strengthening this check to ignore DOS encoded names, but I think it should remain for anything where the realised executable path isn't the same as what you'd assume from the requested path. Without being very aware of how your directories are all configured, it could be near impossible to diagnose, so the warning in the command-line tool is appropriate.