Why is every MC basically a poison/necrotic build?

Ok. Not all of them obviously but I've been making my way through all of the big ones and other than Dungeon Crawler Carl (I think) every main character uses poison and necrotic damage skills as a big part of their repertoire.

Most seem to have moral dilemmas about how they have to kill to survive but the fact they are leaving there enemies screaming as they melt into puddles of goo doesn't seem to register.

HWFWM gets into it early and frankly it's the only one there others even look at the MC like he's a monster.

Don't get me wrong, there's nothing wrong with that as a choice for an MC but in my relatively limited experience it's the rule rather than the exception.

Spear guy? Poison and rot Axe guy? Poison and rot Magic guy? Poison and rot

I'll starting to roll my eyes every time I see it and almost no authors even address the fact that these are horrible ways to kill, glossing over it while the MC is portrayed as the selfish good guy.

Maybe it's just me. I'm still early in my journey but I've probably put in a good thousand hours of audiobooks so far.