It's not that I want the threadiverse to deliver porn to me. I'm capable of finding that myself. It's that I like sex-positive culture and think it's a good thing for humanity overall.
As I noted, my complaint isn't about any specific instance admin. Individually, no one should be required to host or cache anything that they don't want to. However, the overall trend of blocking NSFW communities is still concerning, and we should advocate for admins to not do that where feasible.
The design decision to hide NSFW communities from logged-out users also plays a part here. Community discovery is bad enough as it is, and this makes it even worse. Last I checked, lemmynsfw was having to maintain their own patch to fix it, and keep updating it as new lemmy versions are released. Kbin and PieFed also copied this behavior, and I assume Mbin inherited it.
I've considered it, but my skillset isn't really suited to it as a solo project. I can write code, and I have a reasonable understanding of the human factors side of things, but my IT skills are lacking. I'd be happy to join a team of like-minded people undertaking such a project, though.