There's literally no one competing with their Quest platform, so they'll be in a market position to turn Horizon into the dominant social environment for a whole lot of VR users.
Without cross-platform social systems like this, you end up in a world where your grandma has an Oculus headset and if you want to virtually visit them you need to be on a Quest as well.
BigScreen is another example that I'm glad still exists. Facebook would like to either own them or crush them: https://twitter.com/DShankar/status/1295825811748999173
> When I announced a beta version of @BigscreenVR in 2015/2016, Facebook reached out. They told me to join them, because they were going to build the same thing and crush us.
> I have many stories like this. I can share a long list of VR devs who have been trampled by Facebook.