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Filling the filter with oil has no influence on initial pressure buildup, because there is "rubber flap" one-way valve at the entry of oil filter (visible through perimeter holes).
I think the one and only technical reason for oil pressure/flow not coming up is that there is air below and above pump, now pump acts like air fan and cannot even blow open the filter flap. Flap not opening and air cannot escape unless filter opened a crack.
Oil pumps are positive displacement, not turbine. Air fan effect only applies to a turbine or centrifugal-type pump, such as the water pump (on same shaft), which has lost its prime. They will push/pull air just as well as fluid. 30 years in water supply, we have to know a great deal about every type of pump made. Oil pump in ZX-10R is of the "
gerotor" type. This is why the problem is odd, the oil pump should be creating a strong vacuum and pulling up oil promptly from the sump.
I think the issue is that the sump is not filled enough and the oil pump is sucking air. As someone mentioned, if bike is on a front/rear stand this might be causing oil to be too far forward or back to properly supply the sump. Looking at the diagram of the engine oil system this seems very unlikely as it's locate low in the pan but bike should be level fore/aft.
Warming engine assures good draining and a coating of oil on all engine parts at first start, and good flow when oil pump is trying to get a prime.
Make sure:
-Always warm the engine before changing the oil.
-Add enough fresh oil to ensure a good supply to the pump before starting the engine.
I have never experienced this issue on my 2015 Gen 4 or any other bike but after hearing of it I am always attentive to making sure that oil pressure light goes out promptly. I change on front/rear stands together, bike is level, add oil till window is at upper level before starting engine, and usually fill the filter, then top off.
