I mean I'm proud of my work but conceited is taking it a bit far
I think they're confusing being proud of making one's work with being a narcissistic asshole or an elitist. Liking your music is something that you NEED when making it. My mantra from when I started was to create music I would listen to, mostly because I just wanted some more chiptune in my life, but to also expand upon what others have done and maybe bring some new stuff to the table.
With that said though, there is no denying that there is an "elitist" culture within the scene which I'm sure we've all seen by now, but that has more to do with the medium in which you create chip than content of someone's music.
Chiptune is an amalgamation of many different people, social backgrounds, and styles. It is a scene with all the ups and downs associated with being one. Sure there will be a few people here and there that may feel like they're "100% GRADE A USDA APPROVED BEST CHIPTUNE 2K16!!!11!1!!!1" and that everyone else can go suck a big one, but for the most part, our community is a pretty welcoming and supporting one.
So no, I don't think the majority of us are conceited.