ExploderWizard
Hero
Think about it: D&D was at its peak in the 1980s, with the somewhat mythical number of "25 million" D&D players active. Now whether or not this is true, I don't know. For the vast majority of those folks it was a passing fad, something you and your friends did in middle school before you discovered girls. But a smaller--but still sizeable--group survived puberty and continued on into the 90s (This wasn't the first generation of D&D players, mind you, but it was the biggest - the first being the true Graybeards that cut their teeth on OD&D and B/X in the 70s).
Minor quibble. B/X wasn't around in the 70's. OD&D, AD&D and Holmes yes.