I'm waiting for UPS, should have in hand soon. From various discussions and reviews, it sounds like WebXR in Safari isn't working as expected. However, people are saying this Moon VR player should do the trick, at least for downloaded files. Hoarders UNITE!
Also, I plan to check out the PLAY'A app for iPad, PLAY'A is the app used by the VRBangers family of websites. However, I doubt the iPad app will be able to escape the 2D windowed display that all non-native AVP apps are reportedly locked inside. I don't doubt that plenty of immersive VR players will emerge, and if Safari drops the ball on WebXR, I suspect other browsers will fill the void.