Sometimes you download stuff that relies on case sensitivity. Anyone who's dealt with this probably has a sensitive RW DMG lying around for this reason. But macOS FSes default to case-insensitive, so random issues come up if you make your root sensitive (famously in Adobe software). Damned if you do or don't.

Another weird thing in macOS:

  $ mkdir Cased
  $ cd cased
  $ pwd
  /Users/me/Downloads/cased
  $ cd ../Cased && pwd
  /Users/me/Downloads/Cased

So yeah I wish the FS defaulted to sensitive, even though I never rely on that. Not its job to normalize names.