Well, strictly speaking Linux does too, since it supports mounting local or remote filesystems with this feature
For a long time, the real distinction was that “native” Linux filesystems didn’t support it, but “foreign” ones did. However, nowadays even some of the “native” filesystems have optional support for case-insensitivity (e.g. casefold feature on ext4)
The real difference now: on macOS, it is normal to have this feature turned on, exceptional to have it disabled; on Linux, it is the other way around
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Well, strictly speaking Linux does too, since it supports mounting local or remote filesystems with this feature
For a long time, the real distinction was that “native” Linux filesystems didn’t support it, but “foreign” ones did. However, nowadays even some of the “native” filesystems have optional support for case-insensitivity (e.g. casefold feature on ext4)
The real difference now: on macOS, it is normal to have this feature turned on, exceptional to have it disabled; on Linux, it is the other way around