Can API Return Reverse Results?
Yes, you can, though it's not well-documented!

I recalled that there was some sort of "sort" option, which I confirmed by checked the Using the API documentation.  However, the documentation is incomplete (I'll fix that in a minute).

Fortunately, I found the code that handles this, and saw that you can sort by various field options.  See my screenshot below; I also confirmed that sorting by last_name desc also works.  You should be able to sort by any field.