This is the main point, and almost all the other chatter is not particularly relevant. A dumb computer and a human can agree with "files are case sensitive and sometimes that's a bit weird but computers are weird sometimes". If there was indeed exactly one universal way to have case insensitivity it would be OK. Case insensitive file systems date from when there was. Everything was English and case folding in English is easy. Problem solved. But that doesn't work today. And having multiple case folding rules is essentially as unsolvable a problem as the problems that arise from case sensitivity, except they're harder for humans to understand, including programmers.

Simple and wrong is better than complicated and wrong and also the wrong is shoved under the carpet until it isn't.

Though you still ought to declare a Unicode normalization on the file system. Which would be perfectly fine if it weren't for backwards compatibility.