DMZ2112
Chaotic Looseleaf
I don't think that is a realistic approach to 5E's market, which is far wider than the demographic who find decades' old material from older editions appealing.
I think that is an incredibly short-sighted statement. When I was cutting my teeth on AD&D1 around 1990 I could not get my hands on enough material from the 70s, and between my budget and the available supply it was often extremely difficult. I was fascinated by the history and lore of the game and I think the preponderance and availability of such material to today's audience is only going to fan that flame in the sort of youth who is attracted to D&D.
Today's younger D&D fans, like younger D&D fans throughout the history of the game, are not characterized by the oft-quoted 30-minute attention span. Yes, they are probably chomping at the bit for Halo 5. Yes, they probably post to the internet in a grotesque syntax that only peripherally resembles their native tongue. But these are the kids who spend hours upon hours finding every hidden terminal in the Halo games so they can argue at length about the vague metaplot with other fans on Reddit, Twitter, Facebook, and anywhere else they can find to pollute with their unforgivable newspeak.
You're telling me these fans are not going to be interested in thy /why/ of Tiamat, the Cult of the Dragon, and the Princes of Elemental Evil? I say to you that you carry the burden of proof. Because I don't believe it for a second.