I think you are giving it bigger weight than it deserves. Writing Python code I would not want to depend on internal order of dict elements without a very good reason. If I am writing some low level code that could benefit from it, maybe I would use this feature, but I would then encapsulate it and insert a version check to complain.

This is like many evaluation guarantees in latest C++-NN standards. Good to know, might be useful for performance tuning of automatic code generators, etc. , but irrelevant most of the time. My 2c.