Given the minimum version requirement, I'd rather this support go into a third-party library. (Seems like a great candidate for a context manager, too.)

Recalling our debates about symlinks, I'd have to say that nothing about placeholder files qualifies them as links, regardless of whether Powershell puts "l" in the attributes summary :)

The ecosystem could really do with a Windows-aware filesystem library for this kind of support (and I might already be working on one occasionally, pitching it as a MSFT-supported package, which is why it's not public yet).

I'd rather keep the standard library as lowest common denominator for system interactions, particularly for behaviour like this that is either automatic+surprising or manual+platform-specific and insufficiently compelling (os.add_dll_directory being an example of something that was sufficiently compelling).

So I'm going to mark this as rejected, and steal the idea for my own library :D