Tumblr's being forced to abandon the open policy around sexual content because of structural constraints on the way tech works today.
It's worth reading the post by it's current ceo... Why “Go Nuts, Show Nuts” Doesn’t Work in 2022.
It comes down to three things, credit card companies won't process payments for porn. Even if only a portion of the the content is porn. There are specialist companies that do it, but they charge 20% to 30% processing fees instead of 2% to 3%. Crypto just isn't there for real consumer use.
Mobile phones drive use, apps have push notifications and a much better experience than mobile web. If you want to be easy to use for most people today, you need mobile apps. The appstores decide who and what can be in their stores. To install otherwise on iOS means a tricky jailbreaking process few users will do, and even side loading via fdroid on android is something only very technical users will do. The appstores say they're doing this to protect users against malware, but the reality is this is a tremendous restriction on free speech.
New laws around consent and age verification of people in sexual pictures / video means that it's very difficult to stay legal.
In effect if you have sexual content you need to use a completely different stack for everything.
Does this mean that a privacy centric, no hosting, encrypted social network could fill this niche? I'm not sure. In scuttlebutt's case, both manyverse and planetary rely on appstores allowing us to distribute our apps. The hosting doesn't have a cost, because of the way the protocol works... and we don't have payments. If we do make it easier to use, then I expect we'll be seeing more sexual content as users get driven off of other platforms. What does that mean for us?