Why is there no difference between 2 differently capitalized folders?
History. Backwards compatibility. Customer preference.

Historical Apple, and other, filesystems were not always case-sensitive. HFS+ and now APFS have such capability. That is, they can be case sensitive or insensitive, depending on how it was formatted.

If you are using macOS to manipulate file and folders on a case-insensitive file system macOS will prevent creating same-named files even though their displayed names can include both cases.

Experiment by plugging in flash drives formatted in different filesystems (FAT, ext3, etc) to easily test this behavior.