What makes me very very convinced in my theory is the fact that these people seem to be Superman's friends. Terrific was even trying to get Krypto, and Gunn has referred to them over and over again as his "metahuman compatriots" and made a point of saying that while Clark has deal with the Planet people, Superman has these other heroes, so they're essentially functioning as his superhero co-workers. So if he's already friends with them, and if they're presumably gonna help him during this movie, I don't really see any reason why he'd ditch them aside instead of just joining in with them with a name change or philosophy change something.