So, I think we need to talk about this. Just as we like to talk about how pivotal the early 2000's were in terms of early story game design, the Forge, etc., in thinking about this more recently I think there was a parallel trend going on in the trad world that is under-discussed.
I think that, completely independent of Ron Edward's criticisms, the trad TTRPG world recognized that it had a problem around the turn of the millenium. From TSR CEO Lorraine Williams driving it into the ground (leading to the takeover by WotC, with their own design philosophy), to Vampire the tabletop game beginning to lose out to Vampire LARP, to just overall dissatisfaction with almost two decades of railroaded adventure design as the norm (DragonLance was 1983), there were many people who were dissatisfied with the current state of the art.
I propose that WotC's takeover of D&D from TSR marks the beginning of what we might call the Trad Reformation. (I'd argue that it ends in about 2008, but I'm getting a little ahead of myself.) Let's really consider D&D3.0 (aka "3E"), the first modern edition of D&D.
Fundamentally, 3E was an attempt to do two things:
(1) Have the game make sense mathematically
(2) Because the mechanics would now be reliable, empower players' choices to matter — not thematic choices, but to give players real control over their characters' engagement with the game's subsystems (spellcasting, shapeshifting, etc.)
It's hard to overstate what a wild, wild departure this was from 1E and 2E. Those editions emphasized DM fiat, random chargen, and frankly nonsensical product development. So, even though, as a design, 3E largely failed to meet its goals, they were distinct from those of prior editions—and much more respectable.
Note, also, how much those failed goals of 3E overlap with the Forgite doctrine:
-They wanted to do away with the idea that the GM is god (even though they still made some nods to this in the DMG)
-They wanted rules that would, if followed, deliver a specific kind of experience, reliably
While the Forge has had an enormous influence on the history of TTRPGs, the timing of the Trad Reformation marks it as an example of parallel development, one over which the Forge had no influence. (Much like how Luke Crane and Jake Norwood wrote Burning Wheel and Riddle of Steel completely separately, despite some significant overlap between those games, on several levels!) It was only later on that the two trends in game design could begin to influence each other.
It also isn't the Forge and story gaming that led to the rise of the OSR. The rise of the OSR was in no small part a reaction against the codification and "video gamey ness" of WotC D&D, aka the Trad Reformation.
Since about 2008, pretty much every major development in TTRPGs can be viewed as situated somewhere along or within the triangle formed by Forge + diaspora, Reformed Trad, and OSR. Unreformed Trad has really faded in relevance; while there are still many gamers who cling to the idea of the all-powerful GM, there are relatively few prominent designs that don't at least try to get the math right, that don't at least try to be playable out of the box. Recognizing what happened at WotC circa 2000 is a missing piece of understanding the history of recent TTRPG design.