There's the, "Even I can tell it's a little too much" trope.
What always upsets me with these overpowered children characters is that there's no room for growth. He's like Superman, perfect in every way. But it's that same perfection that makes him so bland. And this kid is only five!
I doubt he'll have the underlying, overwhelming alienation Saitama feels. Or even the worries of destroying everything he loves that Superman has, for that matter.
He's just gonna go around, being god, with no cares in the world.
But, I suppose that is the point.