You can use orgmode in other editors. I use vim, for instance. (Yes, the "official" module is only for emacs, but orgmode is a format and other editors have plugins for it as well.)
The difference between having multiple implementations of a standard and multiple similar tools is that you really can't access the same data from multiple programs or share data with users using a different app.
But Org file and org mode is not the same. Org files you can edit with any editor and with few macros you could speed up such editing, but functionality exists only within GNU Emacs editor, and nowhere else.