DC Comics promised to bring back the pre-52 Superman when it rebooted its universe this year, but so far it hasn't happened.
From a lack of oxygen weakness, to simply not being strong enough, this current Superman is not up to power levels.
In fact, he is more like the less powerful John Bryne Superman of the 1980s.
Why is DC afraid to bring back a strong Superman?
In recent stories, Superman has had trouble breathing and surviving at the Earth's core. He didn't fare well with Doomsday's return and he simply isn't magnificent or powerful enough to deserve the title of Superman.
DC editors -- please conference with your writers and fix Superman, as promised ...