>>531380772
He knows about Freeza, Cell, and Buu so it's clear he experienced Z. All of the movies connect with Z in some way before diverging.
>Cooler being Freeza's brother and Freeza being defeated by Goku
>He's connected with GT which for sure contained all the past villains (see Bejita's flashbacks in episode 55 of GT)
He's definitely a weird composite Goku. That makes him cool.