Volume.

VR isn't big enough to sell enough at the high end for the scale to kick in and bring prices down.

Even at the budget end, Meta sells the Quest at a loss afaik.

And unlike with other devices, like phones, the tech isn't advancing in a way where older devices go obsolete. If you got a CV1, you could still be using it and not really be missing out on that much.

All that adds up to HMDs selling very slowly. The people who wanted one, already have one, and it's probably "ok" which means unless you provide a proper upgrade at a sane price, they'll just stick with what they have. It becomes both really hard to find new VR users, and to sell upgrades to existing ones.