I think that this is better handled per community instead of per instance.
I get what you say about r/gonewild getting ruined by OF posts; OF posts are usually optimised to make you check the link and follow the content creator, so they're crafted in a very specific way to gather attention that spontaneous posts wouldn't, so the later ends overshadowed and the posts feel more and more similar to each other over time.
However, what I feel that the platform needs the most is content quantity; there's relatively little content here, so even OF posts are contributing, even if you label them as advertisement.
And in this specific case we can have the cake and have it too. Since we already know that OF and spontaneous content don't mix well, communities can be geared towards one or another type of content. Just like hentai vs. RL porn, or fetish vs. vanilla. It's also more inclusive because, come on, "you can't post here because you got OF" sounds a bit arbitrary as a restriction.
Note that your analogy with food subs is flawed: food subs discuss food, while porn subs distribute porn. You can't eat a cake online, but you can see porn online. And once we handle this difference, it becomes like @xyth said, it's more like those people are from food companies distributing free food, in a place about sharing free food. (Or rather food kiosks doing it - OF posters are individuals, not companies.)
Just my two cents.
You already did the hardest part - to start the whole thing.
I hope that you find someone whom you trust to pass the torch to.