'King Boar' is looting Dumpster GIF

This is what happens when you take a domesticated pig and unleash it. It also happens VERY fast.

Domestic pigs are descended from boars not the other way around.

When domestic pigs turn feral, they revert back into boars. Since they've been bred for size, they ALSO tend to turn into huge ass boars... and it happens in like 2 months.

You are kind of right. They grow hairy and get tusks but their facial features won't change back into a boars. You unleash a potbelly into the wild it's not going to come back looking exactly like a boar, it'll look like a hairy potbelly with tusks.