The idea that there are future, unspecified changes to dicts() that may or may not be hampered by allowing indexing sounds like FUD to me, unless there are concrete references?
IIRC, first, dicts started preserving order as an implementation detail (implementation borrowed from PyPy?). Then there was a discussion about whether it should be declared that it was a feature that could be counted on -- and it was decided that yes, it was.
So yes -- we can count on it, and so don't be worried about a future re-implementation.