This is in fact a huge oversight in my opinion. As usual Apple's prudishness is limiting them from allowing it but unlike the quest there isn't a side load option either. You're limited to web-based offerings only (and strangely enough WebXR support is not great on the AVP). The experience will be hamstrung by not being able to offer a native app.
And let's be honest, this tech is a game changer for porn. There's a platform called sexlikereal for quest that's doing videos and the immersion makes it way more realistic. You can even couple it with synchronised toys. And this is only video, real 3D content would be even more immersive as you could even move around inside the scene.
You can ignore it or not but SexTech is an emerging market especially in Europe where we have a more open minded stance towards such things. The swinger and poly community is ever growing.
It's a shame Apple is selling themselves short by avoiding a category where AR/VR tech has a huge added value.