Well, just for fun the next time you're driving. Cup your hand into about the same shape and size of one of your piston bottom. Now stick your hand in the wind multiply that by 8, and your fighting normal atmospheric pressure. Would be higher than ambient inside your engine without vacuum. Should you be driving on the moon, you'd feel nothing against your hand. Much like really high negative crank case pressure. Also oil droplets don't spray apart under high vac like they do in normal pressure. So less oil fog to help oil the pins as well. Galling wrist pins was common when people started driving the pressure down. Now most people run coated pins, or .002-.003 pin clearance when they plan for real vacuum. Clear evidence of less oil fog.

Drain back, and oil quality are better with a dry system. For whatever reason, I never have oiling related bearing problems wet. Mopar skirted blocks only provide a narrow opening to scrape the crank. Ford and Chevy are a whole different world giving you access to half the crank.

A good dry system is 4-5G, the best wet is 2G For me I'll run it wet with a pump. The 4.5 seconds I'm on the gas isn't going to make a huge difference in drain back anyway, and my bearings NEVER show any sign of wear from frothed oil.