It sounds like your friend is going 100% off of reputation and vibes, and hasn't bothered to even look into what NetBSD's got going for it.
It literally says on the top of NetBSD's front page that "It is available for a wide range of platforms, from large-scale servers and powerful desktop systems to handheld and embedded devices." Would he doubt that?
Or maybe he sees the word "Net" and assumes it is "for" networking appliances? I dunno.
Aside -- it's been very interesting collecting anecdotes about people's attitudes toward my favorite OS.