I think this is a longterm space that Facebook is definitely not interested in missing out on, so they'll keep it going.
How much does it cost really, in the scheme of things? If anything, I don't know why Facebook simply doesn't ante up and steal some of the talent away from the competitors, they have the cash to do it and I'm sure people would be happy to work under Carmack.
It's clear that Oculus are spending a lot of money on research, and have recruited a lot of people. A key quote from the article is:
"I signed up to build a 30-50 person research team. Oops. Orders of magnitude matter."
So there's at least a few hundred people just in the research team, and probably a lot others in regular product engineering as well. I think it's clear Facebook are pouring a lot of money into Oculus.
To what end though? Say they could spend $10 million and quadruple the resolution, halve the price, and reduce the barf factor of a Rift v2 in a year. What then?
They would probably be better off funding a bunch of people to try to find something compelling to do with the current generation of hardware. It's cool for some types of games, but a market that's a subset of a subset isn't going to set the world on fire. It's easy to come up with a cool demo and hard to come up with a good application.
As a completely separate peripheral? Generally speaking most external peripherals sell to niche markets.
In the current form factor, I just can't see it moving beyond a gaming peripheral anytime soon and the market for that is limited. I was excited when Facebook got into this because appealing to everybody is what they do. But there's been nothing.
I'm starting to think VR is a dead end. There is a market for it, but maybe it's not very big.