There wasn't just no futadom in CoC; there were barely any doms at all in CoC, and not many futas.
You are forgetting Loppe though. i liked Loppe.
Shit, i'm kinda hard pressed to remember one futa dom in CoC.
You had the mouse girl, she was pretty submissive. Urta was more equal. Izma you had to dom the shit out of for her to join the camp. You literally become her alpha IIRC. Marble was kinda dommy i guess, but it's really more like an equal relationship.
The dragon chick was also mostly subby. Anemone kid was also very subby.
There was that one shapeshifting omnibus who you could dominate, but she would kinda reverse dom you? Sera is kinda the same in TiTs if you enslave her and let her keep her dick. Wish CoC 2 had a character like that, i found the dynamic interesting.
The horse yoga girl? She was kinda dommy-ish, right?
Only other ones i can think of are the cum witch and Izma, but letting both of them dom you leads to a bad end.
Damn, CoC 1 barely had any futa dom content now that i'm thinking about it and typing it out. Wonder what caused the shift for the sequel.
CoC1 doesnt really have that many futas in general by default.
I'd say the shift had more to do with TiTs thans CoC1. TiTs had a Kickstarter and a Patreon; it ran for several years after CoC was gone and before CoC2; it had more visibility than CoC ever did - most of the writers that are vets are probably vets of ToTs if anything.
Anyway, futa was always one of Fen's big fetishes, which was why it was in CoC1; but he wasn't the only writer AND he let people donate to determine what he'd add to the game. The audience was more vanilla back then (well, general furry and monstergirl audience) so it resulted in mostly chicks.
TiTs came around and there was more writers, and more cash coming in for whatever Fen wanted to write. Plus, the writers and community CoC had cultivated who liked the unique parts of CoC1 (like futa) stuck around. So you get more futa and more kinds of futa.
Fen got to write more of what he wants, and he like dommy chicks with dicks. This attracts a community that likes the same; the community produces writers who like the same. Thise writers and community roll right over to CoC2.
tl;dr
stuff gets written -> people who like that stuff stick around -> some of those people become writers and write more of that stuff-> repeat.
Writers reflect the audience; audience reflects writers.