Is the file system on an iPad case sensitive?
Yes.
iOS filesystem is case sensitive.
However, the simulator in most cases is not.
You can set macOS to Case Sensitive (at hard disk format time).
But, better do it when you’re newbie, else when you copy files (from nternet, generally), you will get into troubles.
Now, you may install a Case Sensitive OS version n a Hard Disk and boot on it when needed to develop.