I’m very sympathetic to the people who want more D&D releases. I own a lot of D&D books, and I’ve gained great pleasure from them, especially some of the odder releases such as Weapons of Legacy and Magic of Incarnum. I gain great delight from seeing the interesting places the game can go.
However, this is tempered by my experiences in seeing how broken the system can become. Around 2013, I spent a year running a Pathfinder game. Because I don’t have the same affection for Pathfinder and Paizo that I do for D&D and Wizards, I found I was far less tolerant of issues with the rules than I otherwise would have been. I ran two APs to completion that year (Council of Thieves and Kingmaker), the first using core-only and the second allowing more options, and quickly became disenchanted with the optimization required by the game and the adventures. I was growing sick of the optimisation when I stopped playing 3.5E (after 8 years of the game), and Pathfinder seemed to have gone down that route but even more so!
This isn’t to say optimisation doesn’t have a role to play, nor that people who enjoy it are having badwrongfun, but, for me personally, it’s a very dangerous path.
The more options that a game gets, the more likely that optimisation will come into play, especially – as in 3E – the game has a lot of easily combined mechanics. You could write a lot of new classes for AD&D, but because they wouldn’t combine, it wouldn’t cause the same problems that the addition of feats and spells (especially enhancement spells) causes in 3E. With a plethora of options, unexpected combinations occur. If you ever get the chance, try playing a game of D&D with only the original rules (which have a very limited spell list). It’s not really a superior game to what developed later, but it does change your perception on how the game can be played.
Paizo didn’t introduce their “core-only” Pathfinder Society adventures for no reason, after all!
I’ve recently been writing some fan articles on my site to help introduce new players to the Forgotten Realms. I’m not an expert on the Forgotten Realms: I played and collected its products for the first few years after it was released (1987-91, roughly), and have come back to it later. However, my early exposure to the Realms has stayed with me, and I’ve been paying more attention to the Realms recently. I try to research the articles thoroughly, but one thing I noticed very quickly was exactly how much material there is on the Realms. There’s a huge amount. It’s terrifying.
Being an expert on the Realms these days requires a lot of reading. Existing fans, who have stayed with the Realms for years, are in a very privileged position. A new D&D player is likely to be absolutely lost (thus the articles, btw). Just to read all of Bob Salvatore’s Drizzt books requires you to read 28 novels!
(I’ve got a sneaking suspicion it takes less time to watch every Doctor Who episode ever made than to read every Forgotten Realms product).
That’s the trap of producing content: it produces this fantastically detailed world, but at the expense of making it harder for new people to enter it – and, especially, to design for it.
The answer is not to produce no content, of course! We need content. But the middle ground, where the content doesn’t overwhelm us, is something we’re still searching for. The limited releases of 4E’s Forgotten Realms material can probably be considered a failure, as can the jump ahead of the timeline (and consequent “wrecking” of the Realms). Where’s the proper balance? This is what concerns the managers of D&D. They’ve started slowly, but the rate of releases can be increased. It’s harder (nay impossible) to go back the other way!