How the fuck was My Little Pony made in 1705? The company that came before Hasbro was founded in 1923. And the toyline that predated MLP, My Pretty Pony, debuted in 1981.

And now it turns out you were right, sort of. Fist of the North Star started serializing in Weekly Shonen Jump back in 1983. Still after MLP started, but not that far after.