> Sophistication has come to mean a few things, but its original definition was "to denature, or simplify". Today it is common as a measure of refinement
So no, it can in many cases even be the precise opposite of complexity.
It actually originally comes from "sophistry", which is an ancient greek discipline of wisdom and excellence. I would generally associate the word with a high level of complexity that has been expertly reduced and refined to an elegant quality.
But sophistry now means something rather different: using subtle, specious reasoning to deceive.