>>43377the show is anticlimactic to take the piss out of shows like dragonball or sword art. Shows where the character can't lose. The audience knows they can't lose and this makes the show boring, hence Saitama himself is bored by his own fights. He puts in a minimal amount of effort and still cannot lose this buggs him. He dreams or having a real fight, one that doesn't end in one punch.
The show is kept from becoming watch saitama win all the time because no one trusts him or tells him anything. So the show is more about wondering if he will arrive in time.
And it's not just saitama who's overpowered, you might remember the scene where Terrible Tornado (the tsundere midget) shows up and a bunch of the hero's are like 'fuck it, ma jobs done' and go home.