It kinda makes sense, away from any political message being given.
He is an alien. And he does save the whole world all the time.
He should really just have status as Honored guest of earth.
And also considering people see politics as Grey vs Grey vs Grey these days, keeping the ultimate kind hearted super being politically neutral seems wise to me. In the long term.
Short term, I can see Americans raging at this. The idiot ones. I like most of you guys.
But, having Superman as an American doesn't look great to an international audience.
Your government is pretty much universally hated. And that hate influences opinions, even on fictional characters.
Remember the American flags in the Spiderman films? Yeah.
We got a large groan in the cinemas here in the UK.
When one guy swore out loud, we all laughed.
I suspect this will be the reason for the change.
You know, or to generate controversy and get everyone talking about Superman for once and hopefully increase sales.
But a comic company would NEVER do that. Obviously...