Well no I would say Street if you want performance you go stiffer, if you want comfort you want softer and/ taller side wall, and off road I would say softer so you have more articulation not just ridgid.
Think of it like this........ My car for example... take out all of the suspention and weld the hubs to the frame... it would be stiff like a go cart... the chasis would flex little compared to shocks and the wheels/tires would stay mostly flat on the road like a heavy sway bar... this is good for traction on smooth Road surface... the smoother the gripier the road the stiffer and smaller side wall you want on your tires and sus. when racing.... Just like when you have an Off road vehicle:
You have a lift kit... big tires.... big sway bar so you don't tip your SUV over when turning... then you hit the gravel and dirt and offroad territory...... you... exactly "Un" hook your sway bar... IE quick release links ect... this instantly softens up your suspention/ flexion chasis/ body roll.... then you have full articulation and more twist to get around all the bolders and obstacles instead of fighting your chasis your wheels/tires can move freely "INDEPENDANT" of the chasis and crawl over every thing... the softer generally means more move ment... RIGHT UP UNTIL THE POINT WERE THEY ARE TOO SOFT AND CAN'T CONTROL THE WEIGHT OF THE TRUCK... then you aint goin no where as your fenders rest on your tires... Make sence??