That's laughable that you think I'm the minority. Also, it's pretty clear the only customization he was going to be allowed to do in the beginning was his appearance, which isn't a huge concern for min-maxers who will very much wear the goofiest equipment if it means getting the best stats and abilities. He very specifically noted that he didn't care what he looked like, he just wanted to get into the game asap and would adjust things to his liking later. That's a pretty common mentality for many players that are excited about a game. If your appearance normally doesn't affect gameplay (which it obviously didn't before the game became real,) then why bother doing some in depth customization of your looks?
Even if we do go off of the idea that he randomized his stats too, the MC was only a tryhard in the sense that he liked having the freedom to do whatever he wanted, hence his mentioning of his whole PKer phase, he's the type of player that loves experimenting with the game and pushing it to its limits, which is how he got to be the best, you don't get that way by common minmaxing, you get that way by taking calculated risks, like randomizing your build to force yourself to try something different, to see if something that seems sub-optimal, and therefore rather unexplored, can actually lead to some new possibilities, especially since the game has all sort of hidden classes and abilities baked into its premise.
Look, I'm not saying the writing in this series is great, there are some pretty glaring flaws in how the "let's keep the game's story on track" logic is applied (among other issues,) but the randomization choice most definitely wasn't one of them, and acting like it is is just silly.