Don’t understand how pitman and idler arm work at spec torque settings?

Depending on year and model, of course, there could also be a problem with either the K-member bracket or drag link tapered holes. I've seen some tapered holes that had loose components in them resulting in egg shaped and/or totally worn out holes where if you totally tightened up the nut(s) it would bind the steering. When all components are good, correct, and torqued to specs, you should be able to move them by hand.