Some people say things like “I’m gonna do this, and I don’t care what you all think!” but no one cares about what they do anyway. What’s the word for that person?
I’ve considered self-centred and insecure, but I feel those are too broad for such a specific thing. I tried looking it up, but it would give me answers for different things in relation. Compound words and phrases are fine but I would prefer a single word.
Your choice may depend on what you want to emphasize—the behavior, the motivation/personality behind it, or the reaction of others. There are many possibilities.
arrogant
1: Making or having the disposition to make unwarrantable claims of rank or estimation; giving one's self an undue degree of importance. Century Dictionary (1906)
2: showing an offensive attitude of superiority : proceeding from or characterized by arrogance
an arrogant reply m-warrogance
an attitude of superiority manifested in an overbearing manner or in presumptuous claims or assumptions m-w
Indeed, I'd like to suggest that this kind of arrogant front is actually only a more sophisticated approach to avoiding responsibility. By acting in a sufficiently obnoxious manner, you can ensure that nobody will listen to your objections, regardless of their merit. ref
And George doesn't care if people don't like him; he's spent his entire life knowing that. In fact, some of the Arrogant Georges I know consider their unpopularity a badge of honor. ref
