Every car ever built has had compliance steer (once in a while somebody may have tuned it out for one particular lateral load and tire). The body is typically not a great deal stiffer than a hard rubber bush, and I can point you at a rubber bush that is as stiff radially as a tie rod spherical joint, so that's about 3 times stiffer than the body, and 7 times stiffer than a tall spindle. (Ballparky numbers 5 kN/mm, 2-8 kN/mm 14 kN/mm 14 kN/mm 2-5 kN/mm)
Bushings and SBJs and suspension arms behave like springs in series 1/k_overall=sigma 1/k(1...n). You may not be amazed to hear that the stiffness of the wheels and the wheelbearings (to a much smaller extent) is also significant.
What's funny is that all these bignum stiffnesses are being used to control a floppy rubber thing with a stiffness of 250 N/mm or thereabouts, yet their effect is quite measurable both on the K&C rig and the road and subjectively.