Why is the back button disabled on this screen?
Because they want you to exit edit mode first possibly?
Why can’t the edit mode just be an indicator and the back button still exit edit mode?
Good question. Not sure why.
There are quite a few UI elements that don’t make sense to me.
There is a reason the Human Interface Guide exists…..
Hmmm… Human Interface Guide… For a robot… 
For software…. HIG
Thanks for your question. In the current UI, the back button is disabled once you enter the map editing interface. To return to the previous screen, please use the ‘Exit Edit’ button instead. I’ll also pass along your feedback to our UI design team for consideration in future improvements.