It's interesting to note that WSL uses 9p to mount the filesystem on Windows. Had MSFT taken a more FOSS-friendly approach, we could've had a burgeoning FUSE ecosystem built around 9p.
The WSL team in their GitHub have teased experiments with allowing the 9p server to do more outside of WSL and be an open protocol for Windows moving forward. Given Windows' backwards compatibility mandates, you may be able to understand why they are taking a slow and deliberate exploration process to figure out how much that is something they want to support in Windows moving forward (especially if it escapes the realm of "developer tools" where they feel they have more freedom).
WorldMaker|4 years ago