Politics especially.  How many policies are formed that take no account of how society actually works?

Unfotunately there are no reliable theories of how society actuallyworks.

The best the Left came up with was Critical Theory, which is a kind of ritualised distilled Marxism, inbred with semiotics and a lot of quoting.

It's completely useless for real social policy.

The absense of a real theory is why the Chicago jackasses were able to fill the vacuum with their neo-liberal monetarist nonsense. Which is why we're here now debunking the same old talking points about 'reform' when we could be doing something useful.

There have been some attempts to model policy statistically in an empirical and disinterested way, rather than making a priori assumptions about it. But the social sciences are still treated as humanities, not as sciences, which means real research isn't common.

If you want to look at social engineering, talk to the CIA. They seem to have a better idea of how to do it than anyone else at the moment - even if it's only on ad hoc Skinnerian basis, with crude aims manipulated by even cruder means.