Torvalds states the obvious: file systems should be case-sensitive

Apparently, the Bcachefs people are having problems with case-folding, and Linus Torvalds himself is not happy about it. Torvalds holds the only right opinion in this matter, which is that filesystems should obviously be case-sensitive.

Case-insensitive names are horribly wrong, and you shouldn't have done them at all. The problem wasn't the lack of testing, the problem was implementing it in the first place.

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Dammit. Case [in]sensitivity is a BUG. The fact that filesystem people still think it's a feature, I cannot understand. It's like they revere the old FAT filesystem so much that they have to recreate it - badly.

Linus Torvalds on the LKML

It boggles my mind that a modern operating system like macOS still defaults to being case-insensitive (but case-preserving), and opting to install macOS the correct way, i.e. with case-sensitivity, can still lead to issues and bugs because macOS isn't used to it. In 2025. Windows' NTFS is at least case-sensitive, but apparently Win32 applications get all weird about it; if you have several files with identical names save for the case used, Win32 applications will only allow you to open one of them. I'm not sure how up to date that information is, though.

Regardless, the notion that Readme.txt is considered the same as readme.txt is absolutely insane, and should be one of those weird relics we got rid of back in the '90s.