Is there any documentation or discussion on the justification for doing this? I'm scratching my head and asking why anyone would do this intentionally...
Way too ascii-centric. Getting case transformations right in the presence of unicode can be complicated.
Unicode in identifiers is ugly. I never use that.
Helps make code look more like the algorithm it's implementing - would rather just use α than keep spelling out "alpha" every time. Good editors and REPLs make it easy to enter unicode symbols by tab-completing the latex spelling, e.g. \alpha<tab> gets replaced by α.
I don't use nim, so I couldn't point you to the justification. But as I understand it is so an individual can choose his style preferences. myVariable or my_variable.