I read somewhere that it is a symptom of a certain type of artificial muscle-building drug that goes overboard on the chest muscles but that was a reddit comment from a while ago so its probably bullshit.
And there's almost no muscle on that chest. Even if there were, there's no muscle that can get that thick on the bottom ribs (the serratus for instance is quite flush with your rib cage)
There was a story a while ago about how these pictures were staged and designed to show the muskrat in the worst ways possible. It was basically super cheap publicity.
This post is an example of how these pictures propagate and keep that goat a household name.
i have a similar build to him and when i cut out enough carbs for long enough; i look like him; when i don't, i'm just plain old good fashioned fat.
you know he's cutting out the carbs/fat because there's not much back fat; but the chest still sticks out like he is still fat, as it does on me; i would sympathize with him if we wasn't one of the richest men on the planet and a raging asshole at the same time.