They did though! From what I understand from people who made those profitable games is that Facebook funded, either though investments or grants most vr games out there. Even ones not owned by the company (like beat sabre, batman, deadpool, etc).

The problem is, like someone else mentioned, the company itself. Facebook is a middleman company. other people make stuff, showcase it on one of their properties (insta, marketplace, whatever), and then go back to the people actually doing stuff.