I think more people are willing to switch away from Uber/Lyft than from Facebook since (from what I understand about the service) there's nothing really persona

I think more people are willing to switch away from Uber/Lyft than from Facebook since (from what I understand about the service) there's nothing really personal about them except for user ratings. If a new competitor opened up tomorrow that promised to be decentralized with fewer fees, I'd bet on it succeeding. Facebook has many more purposes like communication, media hosting, and event planning (with a very strong network effect). People aren't going to give up on that platform very easily.