Honestly, I'm as tired of the forced 'immigrant concept' as you are of the 'space jesus' concept... and y'know... I also hate the Space Jesus push
Nobody can hear, see, feel what Superman does... but it's all normal to him. He is who he is... and always has been. He looks, sounds, acts American... because his whole (for the most part) life he WAS American. He never REALLY has to deal with the same hurdles as 'true' minorities when he's a handsome, physically perfect white man. People may be nervous about what he could do... but that's not really the same thing. He was never REALLY alone. He had family, he had friends and girlfriends and school.
He may have that 'Nobody understands what it's like to be MEEEEEE' thing going on. But on some level EVERYONE has that. That's not an immigrant thing. Almost every kid in America has bouts of 'I'm all alone and nobody understands what I'm going through'.... If anything that would make Superman MORE relatable.
Though honestly, I much prefer a Silver age superman who revels in the amazing things he can do, Not lament them :P