Sounds more like overconfidence to me. Giving less of a fvck might help you, but ignoring everything might be a disadvantage. Some people might tell you things that are true and for your own good, things you'll miss if you inconsiderately dismiss it. Some things people tell you might make you greater, things you'll not learn if you think you're better.
Confidence is somewhere in between arrogance and humility. Thinking you're great at everything and ignoring everyone else is arrogant. Thinking you svck at everything and believing everyone else is too humble, naive actually. Confidence is knowing when to be arrogant and when to be humble. Knowing what you know and what you don't know. Knowing when to teach and when to learn.
I always try to understand and consider what people tell me, but after consideration I don't always agree. I weigh their view against my own to see which one fit reality the best. I use scientific principles to determine which one is more accurate. I'm not always right and I'm not always wrong. Confidence isn't black and white.