Byrne's whole "Krypton was no utopia" and "Superman may be from another planet but his upbringing on earth and specifically America made him who he is" seemed to be exactly what Gunn was going for here (which, again, makes the whole "Superwoke" complaint baffling)I think from the point of view of the Kryptonians, their planet was a Utopia. In the comics, we did have Byrne's cold scientist approach to Krypton--which might have been Gunn's intended vision of Krypton in this movie. Both the movie and Byrne's stories approach Superman's goodness as coming from his human upbringing rather than any connection to Krypton.