The properties of viscosity hasn't changed ... they never will. A lower viscosity might reduce the oil temperature slightly, but it still could not provide enough film thickness to fully protect moving parts. Engines shouldn't have to fully rely on the sacrificial AF/AW tribofilm. Cooler oil doesn't mean less wear if the viscosity still isn't enough to keep parts from rubbing too much, it just means cooler oil.
What does give less wear is increased film thickness, all other factors held constant. If that wasn't the case, high performance engine makers wouldn't be putting thicker oil in the engines (like the Ford Boss, GT350, GT500 and regular Coyote Track Pack cars, etc) and instead just recommend they all use xW-20. Obviously Ford Performance says use a higher viscosity in applications like track use because even if the oil temperature runs hotter vs a thinner oil, the temperature increase does not negate the added wear protection the oil gives.
One thing that should be realized is that thicker oil results in a thicker film thickness, which means the shear rate and associated temp rise factor from the shear rate is lower in the oil film. That helps offsets the temp rise from the temp rise factot from the thicker viscosity itself. So the resulting temp rise isn't enough to negate the advantage of the thicker film thickness.
In my small engines going from 30wt to a 50wt appears to make them run a few degrees hotter. Not enough of a difference to make a difference.
If my pressure washer runs 270f with 30wt and 280f with 50wt, I definitely want that 50wt in there.
Here's test data showing the oil temperature in a journal bearing with 0W-20 and 0W-30 at different RPM. At 4000 RPM the temperature rise is only 1.5 deg C (2.7 deg F). It's not as much as some people seem to think it would be. As the graph shows, the temperature rise would be lower at lower RPM ... not many people are cruising around...
Only way to achieve that 70 PSI at 6,000 RPM spec for that specific engine is to have an operating viscosity that results in meeting that operational point. The pressure measurement at the location of the sensor directly correlates to the oil viscosity. What oil viscosity does Ferrari spec for that engine, and does that oil pressure spec at 6,000 RPM also call out an oil temperature?
Making a statement that makes it sound like it would be OK to run a thinner oil then recommended for track or stressed condition use because the oil temps will be lower is actually a bad blanket statement.