Also, due to the direction of travel “here: >>>>” and the direction of deflection “?”, the resultant forces are, broadly speaking, in line with the plane of movement of suspension forks : “\”
With most rear suspension systems the movement is either in the wrong plane: “/” or some complicated curved path which is only partly in that plane: “?”
As such it doesn’t work well at all, certainly not like front suspension where you’re getting a ride that is, maybe, 70% as smooth as FS.