Being assertive and standing up for yourself isn't "edgy", that's what you're supposed to do.
Mate, Kidd didn't simply stand up for himself. He slaughtered people, mostly civilians if the consistent bad reputation he gets throughout the story is anything to go by.
You telling me that the moral of the story is supposed to be that if someone makes fun of my ideals then I am wholly justified to murder them?
Shanks is a horrible role model and that scene of his letting himself get dunked on in the bar is the absolute worst lesson for kid's and teens watching the show. Them poor kids now think the right thing to do when being bullied is to let themselves get shit on so they can be like shanks, just for them to keep getting bullied and taken advantage of
All Higuma did in the bar was ultimately throw a temper tantrum and throw liquid around. It wasn't worth somebody of Shanks's calibre to be concerned about.
Heck, the entire incident started precisely because Higuma perceived himself as being insulted by Shanks. I guess thin skinned Higuma was just standing up for himself, amirite?
Then thin skinned Luffy got captured by Higuma because he didn't like Higuma insulting Shanks.
See how being a thin skinned snowflake leads to pointless conflict? Sure, protect yourself when things actually get serious but responding to every slight or insult in your life with physical violence just makes you petty and pathetic. Just like Kidd is petty and pathetic for making a career out of slaughtering civilians that looked at him funny.