Would you care to explain then?
Read the post I quoted. Read my reply. Consider the last question a rhetorical one. The premise is this: the game, when it was most popular was certainly not due to its nostalgia as opposed to good game design, because the game was too new for it to have nostalgic value. Therefore, it must have been something else that made D&D a household name and multimillion dollar industry unto itself. I cited it's ease of use, low cost, and broad appeal as the reasons it became what it was. Now, knowing that the question was rhetorical, who decides what good game design is anyway, do you understand that you and I agree that simple, cheap and broadly appealing might just be that answer? And that perhaps that answer can be measured in terms of sales and/or popularity?