To be fair, Akira is, thanks to Alpha, very much the expert MC with a harem following him around. He saves everyone all the time and no one ever dies. So it's not about reality, but Akira's "cheat skill"-level support.
He also has a much smaller ego.
I mean Akira doesn't really have a harem. He only has one girl actively interested and seeking.
Two of them mostly like him because he saved them, and Shizuka is more of a mother/big sis than anything else.
The women in his life are skilled and don't need him. Elena and Sarah have saved him multiple times and it's shown that they're much more skilled than he is.
My primary meaning is that they're basically opposites in how they handle the world they're in.
Akira goes through the world dealing with the consequences of his decisions. If he's saving someone it's because they matter, or it's the mission, and usually he's taking an ass beating to do it. Nothing he does is free, and he doesn't behave as if he's in a carefree world where he can just "save" people on a whim.
He acts as if he could lose his life at any point and he's only where he is because of Alphas support.
The other guy is the exact opposite.
It's easy for him to save people, he doesn't seem to have to face the hardship while doing it. In fact he's arrogant about it, ignoring how he puts himself in danger and drags his team around to risk their lives as well.
He genuinely seems to be very skilled. So much so that he can afford to drag along weak girls who's primary role is to support his ego. They don't grow, they don't teach him anything. They're just there, following him around.