I don't believe that no explanation exists for the "butterfly wing" kind of complexity, I merely believe that such an explanation is not yet known to any human, owing to the large magnitude of that kind of complexity, and so we frequently use terms like "randomness" to brush over those kinds of gaps in our ability to explain things and impose boundaries between what's known and what's unknown.

I agree that some complexities in the area of culture like law, religion, political institutions etc. are self-referential and ultimately serve no purpose or are even counterproductive relative to their presumed purpose.

The important thing is that I wouldn't attach a negative value-judgment to complexity, like saying complexity is always evil or bad or serves nefarious purposes. It is precisely the unwillingness to engage with complexity that perpetuates it.