I don’t know firsthand, but many of not most people with abnormally large penises (8+ inches or 20+ centimeters) have stories of sex with people with vaginas that was uncomfortable for at least one partner if not both. Most vaginas have evolved to accommodate penises within two standard deviations of the average, which the vast majority of penises are. If you’re jealous of people with pornstar size penises, it’s usually because porn had conditioned people to overlook the potential problems that such size can cause. It can be too large to fit properly and if you’re not careful, you can injure your partner if you’re as rough as you usually can be with a more normal size. If you’re around average, you’re perfectly fine to fit most vaginas, and people with vaginas that prefer the larger penises are fewer and farther between than you might think.