Why | is forbidden in Creative cloud

I use a pretty common folder naming for photographers - Photos Go Here main folder with mm-dd | Project name. This keeps all the dates & project names very neatly & is easy to scan. Its been recommended for years on many photo sites.

However | (thats the shift \ key) is a forbidden character when uploading to Creative Cloud so my files don't upload. Of course I could use another character but to change my entire archive? bit too much when iCloud & Google drive don't have this 'problem'.

Any way round it without me renaming every folder?