So I'm the wrong person to respond to this, given that I don't run nowadays in fandoms big enough to have these issues; I'm going to run your hypothesis by my friend E, who has been moving in big but very different fandoms (Reylo and now BTS) and see what her take is. (Also E is very active on Twitter and has a much more positive experience of it than I do.)
(I feel like it's also easier to have "huge fandoms" now? My husband was in an anime-focused 'zine in the mid- to late-90s, even though the idea of anime by itself being so niche as to be the focus of a zine with two dozen people would be laughable now. Buffy didn't feel like a huge fandom at the time; it felt like me and two separate groups of friends who loved the show. Now the mechanisms of creating a fandom are so well established that it may be hard for an interest with mainstream institutional backing to feel niche.)
My recollection of early 2010s Tumblr was there was an underlying tension about credit -- not cropping the logos out of fantaken photos, complaints about ideas being stolen, et cetera. I wonder if that + fandoms going over Dunbar's number is what's bugging you. Nowadays a fandom can grow so quickly that the meta-writers can't find each other before their experiences are swamped, and if they do find each other, then it's harder to establish mutual trust. Maybe? I'm not sure. I'm glad the Kinnporsche meta writers were able to find each other.
no subject
(I feel like it's also easier to have "huge fandoms" now? My husband was in an anime-focused 'zine in the mid- to late-90s, even though the idea of anime by itself being so niche as to be the focus of a zine with two dozen people would be laughable now. Buffy didn't feel like a huge fandom at the time; it felt like me and two separate groups of friends who loved the show. Now the mechanisms of creating a fandom are so well established that it may be hard for an interest with mainstream institutional backing to feel niche.)
My recollection of early 2010s Tumblr was there was an underlying tension about credit -- not cropping the logos out of fantaken photos, complaints about ideas being stolen, et cetera. I wonder if that + fandoms going over Dunbar's number is what's bugging you. Nowadays a fandom can grow so quickly that the meta-writers can't find each other before their experiences are swamped, and if they do find each other, then it's harder to establish mutual trust. Maybe? I'm not sure. I'm glad the Kinnporsche meta writers were able to find each other.