I was once told I have "generic" lineart, whatever that means lol. I agree a lot with claiborneart, style is something that's constantly refined and mastered over a person's lifetime so that it eventually evolves towards something inherently specific to that individual. But, that's also not the route everyone takes depending on the purpose of their artwork, as some make it their career to work within styles that draw mass appeal. Either for their own products or a company's promotional material.
I think there's another factor at play here though. It's just going to work out that no matter how good you get, how true to yourself you try to be, we can't control how other people perceive our work. They'll think us this way, that and the other, and there's nothing that can really be done to change that other than just recognizing that give and take. If some like our work, others just won't. I have my own biases and what I might consider 'generic' another would consider to be their unique mark on the world. That's the thing about perspectives, you're going to be fighting tooth and nail to prove who's is rooted in fact.
But if someone just straight up told me my stuff is generic (like they did do), I'd brush it off. What use does a vague statement like that have as a kind of feedback? "It's generic, don't be generic." I can't please an opinion, I wouldn't even know how to begin.