In the Save File As dialog of most Windows apps, you can enclose the filename in double-quotes to force it to not add an extension. I wonder if that will help with the issue in macOS?
1. Put some of the forbidden symbols in the file names of, let's say, a bunch of photos.
2. ZIP them
3. Send to someone who ordered those photos with Windows/Linux computer.
4. An hour later tell them that everything works on your computer and you don't see the problem. As a bonus you can film unpacking the zip file and saying: "You see, it works. There's something wrong with your computer".