There's no issue at the upper limit, rather at the lower limit... pressure could drop too far, doesn't matter if you're pumping the same gpm if you leak it out as fast as you pump it. In any case you need to know what the new normal is.
The supply oil pressure seen at the inlet of the oiling system is primarily a result of the flow resistance of all the journal bearings. Look at how journal bearings operate. As long as there is an adequate supply volume at the bearing inlet to take in while it's rotating, then the bearing will flow oil and produce a MOFT based on the oil viscosity - the thinner the oil, the more volume the bearing will flow but the MOFT will also decrease, and the lower the indicated oil pressure will be.
It's possible that the lubrication will be inadequate from the actual viscosity, but not from the oil pressure as long as there is an adequate supply volume so the bearings are not starved of oil. Lubrication of all non-pressure supplied (splashed) areas of the engine like cams lobes, rocker arms, cam chains, piston skirts, piston rings, etc again depend on the oil viscosity to provide an adequate MOFT, and as long as an adequate volume of oil is supplied/splashed on the parts it doesn't really matter what the supply oil pressure is.
Like said above, if there are mechanical mechanisms that are designed to operate with a minimum oil pressure, then obviously there will be a point where the oil pressure will be too low to correctly operate those mechanisms. But otherwise, if there is adequate oil volume there is adequate lubrication as long as the actual viscosity results in an adequate MOFT. That is why "oil pressure does not equal lubrication" when the oil volume supply is basically constant due to the PD oil pump. An engine could have relatively low oil pressure but still be supplying a ton of volume. Only when the oil viscosity it too low to provide an adequate MOFT is when lubrication is failing. Yes, lower oil pressure means the viscosity is lower, but oil pressure can't be used to determine what the MOFT might be due to the actual oil viscosity between moving parts.