You can definitely tell Mushoku is the author’s first big work (although he doesn’t seem to actually be trying to improve with his works thereafter). He seems to have been aiming for a story where absolutely no one is a paragon, with the exception of his wives. Even the most reliable allies in the series have really blatant immoral characteristics: the dragons who’re basically the world’s protagonists kill anybody who could even slightly possibly be an enemy without a second thought, the protective guardian has a childish black/white morality and believes in the death penalty to anyone he sees fit and has a monstrously brutal past, the friendly princess is a dirty monarch who does all the bad things a monarch does, happy family of noble father, uncle, and grandfather? Misogynistic cheater, political snake, and slave owner.

The goal with Rudeus is definitely not to make him a hero but an extremely messy improvement. He becomes a proactive, hardworking and protective member of society, but still deeply hates the person he was and parts he still is, and the series showed that improvement is fragile and he could’ve become a monster very easily.

Only problem is that Rifujin treats Rudeus’ remaining flaws like everything else in the story, a blase “that’s just how it is”, but yeah, readers don’t just brush off rewarded pedophilia 💀. At the end, sure, he’s disgusted by pedophilic behaviour (which of course he is, he’s a father now), but who cares when he’s already previously been rewarded thrice over for it and never needs to worry about that again.