You have absolutely no idea what you're talking about. Facebook is, far and away, the biggest funder of VR games. It has nothing to do with Horizon Worlds. Most of the large studio VR games that do exist, do so solely because they were partially or fully funded by Facebook's creator funds. VR games don't make any profit, so nobody wants to develop for it.

They're also the only company that sells an affordable headset. I hate to break it to you, but nobody's going to create games for systems that have no consumer base. Hell, even with the large success of the Oculus headsets, the players base is still too small to warrant development in the space (that's entirely why Facebook has to fill the void in the first place).