I'm not really disputing your broader point, but this:
> Porn is what got VHS to succeed over Beta.
Is just not true. For one, porn absolutely existed on Beta. But more broadly, by the time the content available on each format mattered, VHS had already won the format war.
That's because both Beta and VHS were primarily developed and marketed as a way to record TV to watch later. Tapes were way too expensive to make selling pre-recorded tapes viable when both systems launched. Pre-recorded tapes eventually did become popular, especially in the rental market. But that only happened well after VHS clearly won the format war, mostly due to VHS's longer recording time.
It's not that immersive because you either get a video that you can't interact with where you get to play the part of dead fish wearing a camera rig, or it's absolutely insanely bad 3D models that will only ever get deeper into the uncanny valley. The videos are also terrible quality because making VR porn is expensive, and if you prefer somewhat amateur content, you are completely out of luck, because couples moonlighting porn aren't buying those camera rigs.
I have shown VR porn to many people. They go "woah". I tell them they can have a similar experience literally on their phone with a normal $30 phone holder "headset", none of them buy the headset. None of them even try it ever again.
Very very few whales are optimizing their porn experience. The vast majority of human beings simply scroll through pornhub for 12 minutes and watch half of two videos and then continue their lives.
"Immersiveness" is not a strict benefit for everything.
I found a single VR porn website that worked with the AVP. It was super finicky (around 30 seconds to load a page and actually get it playing, involving 6 button presses). Also was a paid website.
Porn is what got VHS to succeed over Beta. Porn is what got CC payments working online. Porn drives a lot of Twitch and other platforms.
Apple won't allow porn on its platform, but someone will.