> IMO, economics as a science is all about making up theories to 'scientifically' (but actually, just academically) justify whatever the ruling powers want to do.

I see this with macroeconomics, but economics is still a fairly broad field. Microeconomics has the spherical cow problem but econometrics has many useful applications, as does game theory.

A piece of evidence to your point is who quant firms hire: a lot more physics and math PhDs than economists. You would think someone who studies the science of the economy would be good at making money, but the real economy doesn't seem to care as much about those theories.