Oh, I don't doubt the lineage connections. But check out any number of McDojangs and you'll probably find equally illustrious connections amongst school owners, operators and instructors who operate on a belt-for-cash basis. I'm dubious about the notion that the overall quality of TKD instructruction is higher than that of other MTs to a degree that would give rise to the enormous statistical imbalance between, say, Muay Thai, Gojo-ryu or Southern Mantis kung-fu on the one hand and KKW TKD on the other. Media attention and awareness of TKD, based on its vast world competitive network (in turn based on its Olympic status) almost certainly plays a big part. When you're primarily known as a sport, you're going to get a lot of attention in popular culture—these days, anyway—that you otherwise wouldn't.
Here's a little example: when I go home to visit my mother on LI, the drive to Trader Joe's to buy groceries for her used to take me past Tiger Schulman's Karate. No more. A week and a bit more ago, making the drive once again, I had the horrible realization as I passed the block where it used to stand that Tiger Schulman's Karate was...
no more. :waah:
But there's a silver lining here. Like a phoenix, in the place where ol' Tiger's house of pain used to stand, had miraculously risen in its place...
Tiger Schulman's MMA. Astonishing, eh? Somehow, that wily Tiger had been way ahead of the curve and had spent years of study mastering the new MA which he foresaw would come to replace karate in the popular imagination. I mean, if he hadn't done that, how would he have become qualified to teach this totally, radically different new combative activity?
I suspect a lot of TMA places have retreaded themselves as MMA places, out of necessity: there is a lot of cultural awareness of MMA, much more than of Karate or the other arts I alluded to, because of media attention. And TKD has benefitted from that kind of media attention for a long, long time, as long as the news media have been aware of it as an Olympic activity. People may not be aware of the fine points of the Olympic events themselves over the past decade and a half, but—as you yourself note in the part I've bolded above—they are aware of TKD as a competitive sport, widely practiced. And that's largely because of the Olympic-based media publicity that TKD can command, and which the other TMAs I mentioned cannot. So while it may not be the whole story, I myself suspect that it's a big part of the whole story...