There's a lot more in the Genesis version that got removed to fit the bigger sprites, and it wasn't just Earthquake or his stage and theme song. A whole lot more than that got the axe.
Hypothetically speaking, if he existed, he probably would've been the fattest person in the world at the time of Samurai Shodown. Guinness world record stuff lol.
It's the stupidest thing I've read, the genesis version doesn't include Earthquake as a selectable character, therefore this theme and stage doesn't exist in that version, dirty sega fanboy.