With NTFS you can enable or disable case sensitivity. Is there a way to do it with ext4 in Linux?
There are patches currently under development to implement case insensitivity for ext4, but they are facing some headwind from Linus, so it isn't clear if/when they will land.
Nope. Under linux you can do that to fat,vfat,hpfs,ntfs and to iso9660 w/ rockridge extensions. All linux (unix) native file systems I know are case-sensitive.