HFS+ can be configured at creation time to be case sensitive. I did so a while back. Worked perfectly except for one application which could not find it's files. So i had to create a container and Format it case in sensitive and intall the APP there...

I used to format my whole disk as case-insensitive but enough poorly written apps broke (ok, mostly Steam) that I now just have a case sensitive partition for my source code and /usr/local.

Adobe apps are notoriously incompatible with case sensitivity. If your apps work, that's great. But if Apple switched to case sensitivity by default, it would break apps.

Apple breaks apps all the time on macOS.

This is for iOS, where the app developer fully controls file naming within their sandbox. It is very unlikely that MacOS will fail to normalize because filenames there are presented directly to the user.