Maybe Zuck’s “Just keep throwing money at it” strategy ain’t all that.
Much of that is from the hardware, a very conservative estimate of (Quests sold by mid-2023) * (typical ~$300 MSRP) gets you to $6 billion revenue by itself. The problem is they're selling the hardware at a loss, and their attach rate is abysmal so that gamble isn't being offset by software sales. Most Quests ended up gathering dust.
When I get another headset it will be a PC-VR dedicated one, because my use case is clearly not what they intend. Their Link app is an abysmal experience and updates tend to break things and just make it worse. A third party app, Virtual Desktop, is plain better in every aspect, but still hampered by the general poor UX.