This approach is too complex for what is provided. You're better off just making a copy of the tree and simply using sandbox-exec. macFUSE is a shitshow.
The main issue I want to solve is unexpected writes to arbitrary paths should be allowed but ultimately discarded. macOS simply doesn't offer a way to namespace the filesystem in that way.
The main issue I want to solve is unexpected writes to arbitrary paths should be allowed but ultimately discarded. macOS simply doesn't offer a way to namespace the filesystem in that way.