99% of OnlyFans photos have altered dicks. It's ridiculous because it's so obvious when you notice the size difference in other photos taken before OnlyFans, or unedited videos where it's much more difficult to make a dick look bigger.
Mario and a few other creators have used lens effects that make certain parts of video frames look bigger. If there's any weird, cut-heavy editing, blurring or stretching effects, or even if certain body parts appear abnormally large within a frame, you can be certain that you're not looking at a natural, unaltered image. E.g. there's one video in particular that looks like it was filmed on a camcorder in 1991 where Mario's dick looks huge, but his hands are also as nearly the same size as his torso. It's clearly altered.
For someone that talks so much about being proud of his average endowment, he sure seems very insecure about it. It's stupid though. He's not going to lose subscribers by being honest.