Larger lenses require support. PL lenses are big. Little lenses don't require support.
Most nikon lenses are little, especially compared to PL counterparts. I don't expect to have to provide any lens support except on my telephoto nikon 80-200, which is pretty big.
My understanding of lens support is that if you don't do it, the weight of the lens puts torque on the mount which can
a.) put unwanted wear on your mount and
b.) could be significant enough that the focus/sharpness of the lens can be affected
My question is, are nikons, even the big telephoto, small and light enough that support isn't really necessary? I use the 80-200 on my d2x all the time without much support without a problem.