I've been playing video games for some 29-30 years, and I've also come to despair of the current farce that is the hardcore versus casual gamer. I'll exemplify my opinion with the statement that chess is one of the most "hardcore" "casual" games you will ever play. I contend that what distinguishes a true hardcore gamer from a true casual gamer is not the particular game or kinds of games they play; instead, it is their approach and level of immersion into the lifestyle of gaming, i.e. their enthusiasm for gaming, that truly distinguishes them. Thus, I think more appropriate labels would be "enthusiast" and "non-enthusiast", with no accounting for experience with the gaming lifestyle and culture(that's handled by labels such as "newbie", "pro", and "expert"). These labels are not intended to distinguish who is the better or more worthy gamer; rather, they are intended to denote the level of commitment a person has to the lifestyle of gaming, balanced against all other life obligations.
In my opinion, it is the so-called "hardcore" gamer crowd, as it has come to be, that is really more responsible for the contraction of innovation and variation in gaming. Basically, if the game is not some variant of Grand Theft Auto, God of War, or a first person shooter about space-marines, featuring a color palette of butt-shit brown, suicidal-depressive gray, or snot-puke green, then it's just not accepted as a viable and fun game. Also, the hardcore crowd doesn't seem to accept a game unless it is designed to completely monopolize one's time and energy(as far as I have seen, game developer's have been accomplishing this not with increased content requiring extended play but, rather, by using time wasting gimmicks in the design of the game). These attitudes seem to uniformly permeate the current "hardcore" crowd, and this crowd seems to have the loudest face in shaping the direction of gaming. Finally, the bigoted, infantile hostility of the so-called hardcore gamer crowd is definitely not conducive to bringing more people into the gaming culture, which would give more legitimacy and acceptance of gaming within the larger social context. Instead, it serves more to isolate gaming and return gaming to the closeted and highly stereotyped state it had during the 90's and early 2000s. This is ironic considering the more social, and even family-oriented, state of gaming during its earlier years(just think back to the days of the big arcades). In short, I contend it is really the current so-called hardcore crowd that is actually bad for gaming.
From what I see, the so-called casual gamers can actually offer the opportunity to breathe new life into the gaming industry by providing a market that is not inbreed to same basic games or kinds of games. Also, these casual gamers, having the opportunity to be more well-rounded in knowledge, experience, and attitude, can bring new ideas into the gaming community and provide new perspectives on gaming with the greater context of life and society.
In my opinion, the so-called hardcore gamer crowd need not fear a sudden deprecation of their favorite game or game genre. If there is a market for a particular game or kind of game, there will be a developer that will make it(just look at game like Rapelay and shudder). It may not make the front cover of all the gaming magazines anymore, but it will still be out there. What the infusion of so-called casual gamers offer is the potential market support for experimental games that attempt to extend into new areas of gameplay outside the space-marine first-person-shooter, GTA clone, God of War clone, or city racer.
Ultimately, games, as we have come to know them, are about having fun, regardless of any labeling. If a person plays games on a regular basis, then that person is a gamer. Period. We each have a different definition of fun that we each decide, and we seek games that satisfy that definition of fun. The distinction of "hardcore" or "casual" is unimportant and undefined in that context. This elitist, separatist attitude dividing the gaming community into so-called hardcore and casual gamers is nothing but a farcical rationalization of self-importance; simply one group stoking its own ego to think itself superior to another for no truly justifiable reason.