I'm baffled by this controversy, to be honest. It should be noted I'm not a comic book fan, and in my youth I only read Mad Magazine and occasionally Archie comic books. I never got into Superheroes or the whole comic book scene. Instead, as a 12 year old boy, I have distinct memories of reading and laughing at the one panel comics in my mom's subscription to
The New Yorker, which is weird.
That said, I did see the original 1978 Superman in the theater and have seen it again once or twice at home, and have vague memories of seeing one of the sequels decades ago. But... Superman is now an immigrant??? When did that happen?
I thought Superman was an alien from the planet Krypton, and was
not human but coincidentally looked human and even more coincidentally was very handsome with chiseled features and piercing blue eyes.

And his parents on Krypton shot him into space before his planet was destroyed to save him, and after his space cradle crash landed in a Kansas corn field, he was taken in by a married couple who couldn't have their own children and was raised as an average American child in small town Kansas who just happened to have superpowers owing to him actually being Kryptonian rather than human.
Right? What am I missing there?
In this new Superman movie about to come out, is that no longer the story? He's now a human, and an immigrant from another country who sneaks into the US illegally and is found out, despite his superpowers? They changed his backstory???