A hypothesis based on porn. Sigh.
A little over a year ago I dated an underwear model. Met him on Grindr. He sent me pics...great bod. BEAUTIFUL fat, uncut cock. In person, he was built like most of the male porn stars I've met over the last 20+ years: small, compact bod. Gregorio was 5'7", 135lbs. His cock, which looked big in pics, was actually on the small side of average. If you looked at our pics side by side, you'd think my dick was smaller due to my thick bod. In person, mine dwarfed his.
Porn isn't real life. I repeat, porn isn't real life.