That's somewhat true, but I've been gaming for 22+ years, and I never saw anything even approaching the level of CharOp-type madness until 3.x D&D came along.
Now, I'm not specifically blaming that on the design of that particular game system. Not at all, really. That was more of an accident of timing, combined with opportunity.
I think it has everything to do with the rise of computer video games, especially MMORPGs, and to a smaller extent, the rise of Magic: The Gathering and its many clones.
Character optimization makes nothing but pure sense when you're facing an entirely inflexible computer "DM" which simply presents the highest-end challenges at a level which makes them (practically) impossible to overcome without squeezing every last advantage from the game's mechanics. When you add into this the element of competition between players, it is only natural that the "extreme ultimate totally ludicrous character optimization" mindset would arise and become more or less the standard.
It is rare to see old-school gamers, who have not gotten into computer games or collectible card games, or been significantly influenced by the players of those kinds of games, engaging in the kind of ultra-hardcore character optimization fanaticism that is so widespread now.
This is simply because, in classical pen-and-paper gaming, such a degree of mechanical efficiency was never really needed. You weren't, usually, ever really competing directly with other players, at least not for long, and not as a general rule. And you were always facing dynamic challenges which were, ideally, more or less custom-suited to the capabilities of your characters, with a living, intelligent human DM who could adjust anything on the fly to fit the game. So if you made "concept" characters who weren't necessarily the baddest thing on the block, it was okay, because the expected game content was never all that hard.
High-end raid content (or high-end PvP) in an MMORPG isn't dynamic or forgiving. Either you optimize to the highest degree, or you fail. Furthermore, you're in a social environment where you're competing for raid slots, or competing directly against the strengths of other characters in PvP, so once again, it completely behooves you to make your character as mechanically effective as possible, and massively disserves you not to.
These ideas, I think, have just sort of filtered into the mindset of pen-and-paper gamers, as well, over time. Many modern gamers now consider it just a given that you'd make the most combat-effective characters possible, because in the overall community of RPG-type gamers, that's the prevailing idea of the most "logical" and "beneficial" thing to do.
Sure, 3.x did make it easy, by offering so many options and so much flexibility in character building that it really lent itself well to CharOp-type tactics. But I don't think the game itself caused the colossal surge of CharOp thinking. I think it came, mostly, from outside of the tabletop gaming experience.
I, personally, can enjoy both kinds of games. I really love playing more role-playing and story-oriented campaigns, where I'm free to craft a meaningful character without worrying about whether or not I'll be powerful enough to handle the game challenges. I can also really get into and enjoy playing high-powered tactical combat-type games, where you can get the satisfaction that comes from system mastery and its rewards. So I get both sides.
The problem only really arises when you have a mix of these types of players in one game, and neither are especially flexible in their playstyle. That quickly turns into something like this:
[ame="http://www.youtube.com/watch?v=zFuMpYTyRjw"]Angel Summoner and BMX Bandit[/ame]
(Or, as I call it, a Needlefang Drake Swarm Summoner and Halfling Mace Fighter situation, in 4E terms.)
That's no fun to DM, and rarely fun for the players.
I do like the fact that 4E appears to have at least partially mitigated the rampant CharOp-ability of the game. It looks more balanced (largely due to greater restrictiveness), but only time will tell.
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