According to [1], Mac supports using slashes as part of folder names (they use colons instead). So there might be some circumstances where that decision comes back to bite you, if you ever port to Mac.
To see this in action, open a terminal, type:
touch test:file.txt
I'm not sure which is the native representation, but I do know that every API I've used to interact with the filesystem on macOS has used slashes as the path separator, so GP should be fine. But it's definitely a fun party trick to pull out around unsuspecting Mac users.