I think what he's getting at is that there's a lot of people who refer to themselves as 'Hardcore' Gamers as some kind of elitist label.
Which I'd be inclined to agree with.
for me it is not about that. For me these definitions are an indication of peoples habbit and on what they spend their money on for example. And normally it is a given fact that gamer have a bit more knowledge about games then the casual Mario kart or GTA player. You will know about upcoming games, you read previews watch videos, trailers etc. It is just an indication how much you know and how much time you spend with gaming related stuff.
I didn't imply all gamers who refer to themselves as 'Hardcore' are doing it as some ego boosting effort, just a large number. You may do it for all other types of reasons, though I can't think of any I wouldn't interpret as ridiculous.
Would someone who had the same passion and knowledge for films (like me) label themselves a Hardcore Cinema goer? Probably not, and even if they did I wouldn't take them serious.
But 'Hardcore Gamer' sounds 'l33t'. Now, I'm not suggesting for a minute that you'd refer to yourself like that just to sound cool... but why refer to yourself like that at all, why refer to yourself as anything because of a hobby?
It's the gaming equivalent of a personalised license plate - it's an immediate signal that the bearer is probably a total douche.