Depends on where you're measuring it, but in general 45 at idle suggests very high viscosity (normal if the engine is cold). At idle the pump isn't moving that much volume. If the measurement is close to the pump, high pressure means that little volume isn't flowing up through the engine.
When the pressure is high because the oil is too thick its like this.
View attachment 1715779229
It's not getting more flow to the top no matter how much pressure is added.
