You know, it varies for me. In one sense, I consider anyone from 2a to 4b to be in the curly family.
But, it does feel weird, mostly IRL, to hear a 2a or 2b complain about having very curly hair or unruly curls because when compared to me, their hair is more wavy.
But the reverse holds true as well. I'd feel weird complaining about how curly my hair is to a type 4, when she'd probably be wondering why someone with a relatively loose curl pattern (compared to her) would be complaining about tight curls.
The only time it bothers me here is when someone asks for typing help, and they refuse to believe the 15 posters who told them one type, insisting that it is really something else.