The economy as a complex system is appealing. The idea looked very promising in the early 1990’s when I was a grad student. Unfortunately, it has not led to any meaningful (i.e. practical/usable) results. Just this month came across an attempt to model insurance markets using an agent-based model. The paper was co-authored by an eminent proponent of complexity theory etc. Unfortunately, the authors trip all over themselves when trying to actually calibrate or relate their model to real-world conditions.

Complexity theory is a useful thinking tool, but has yet to bear fruit when it comes to making statements about future system behavior.

Likewise, econophysics was a thing fifteen years ago, but now only survives in academia.