Umm... what the heck are these choice of examples. Mainly we are talking gaming VR devices. we can basically scrap the "metaverse", apple, microsoft, google glass off the list.

Virtualboy? we're talking an attempt to make VR in the days before anything close to a viable technology even existed.

Realistically the products I'd say are actually, modern VR gaming are more or less oculus, valve index, and maybe the playstation VR thing?

Really though, not a huge shocker that sales are declining, as a gaming niche, I don't see them as the kind of thing people are likely to upgrade on the regular. Least not unless/until someone majorly blows away the weight/bulk of them. Say take me, I'm probably a typical user, I bought a quest 2, about 3 years ago... happy with it.

am I buying a quest 3, nope, bought my son an index as a big christmas gift 2 years ago... is he going to upgrade his, probably not.