Here is an excellent overview of roleplaying games from the other end---ie: broad categories of play cultures, and their historical contexts---which I think would colour in the missing "contact with human players" side of TTRPG theory:

https://retiredadventurer.blogspot.com/2021/04/six-cultures-of-play.html

I'm relatively bad at talking about this stuff but I WAS THERE MAN

as someone who was there and misses talking about it, i'll talk, if you want!

i think you're generally correct to say "Games do not neatly fit into the GNS (gamist, narrativist, simulationist) categories, and that doesn't make them incoherent either." i think the biggest flaw of the presentation of GNS was the rigidity of the boundaries, and the categorical dismissal of most gameplay as "incoherent". (or if it wasn't dismissal, it sure came across as such)

i think it might help to consider that GNS theory as such was not designed to describe, like, Game Systems. but rather, it was an attempt to taxonomize how different groups of players sat down and played games. so like, one group can theoretically be playing a Gamist D&D campaign, one group can be playing a Simulationist one, and one group can be playing a Narrativist one.

and, even if these groups start with the same edition of D&D and are referencing the same books, the theory implies that these three separate groups will, over the course of play, alter the actual rules they are playing by to be a better fit for their desired style of play. and this process is called "drift".

it's a lens! it describes a lot of things people do when playing RPGs really well, and some things not so well.

but mostly it was kind of the albatross around indie-rpgs's neck; it was supposed to be a minor part of the whole affair, but people kept asking about it and arguing about it and then it became an ideological marker and a group status symbol so it ceased to function usefully as a communication tool. but maybe it's time for a return.

I really miss the Forge.

If I were to be objective about it, game design does tend to be more refined these days, and the numbers of weird little ideas posted all around the net are incomparable to ever before.

But also, it feels like things were fresher, bolder, more experimental back then. This likely isn't true in the objective, numbers-and-facts way, but it's more about the kind of statement piece games that were big back then. Nowadays I think all the pioneering work gets a little drowned in the indie-mainstream of a handful tentpole systems and trendsetters and all the hastily shat out itch.io microgame plankton.

Its probably just boomer reminiscing about some games and times I consider fairly formative for my ttrpg life, but I can't help but feel something was lost from that era's way of thinking about game mechanics.