It is not the anti-monopolistic authorities (who are part of the system, anyway), but WE_THE_PEOPLE who need to do something, so that competition is assured. WE need to keep switching services and not let one service rule everything.
Be it messengers, social networking apps, eCommerce stores, ERP software, anything - If we choose one organization to rule them all, it won't be very long before they start showing the traits of that one Saruman's ring that rules them all.
Yeah, that's not going to happen. The majority of "We the people" is made up of those who take the path of least resistance.
Facebook, by doing things like this, will only hurt themselves. We've been down this road before with Microsoft. It is anti-trust, and will get them in a lot of trouble.
It is anti-monopolistic authorities only purpose to do just that. And it is an important role to keep the economy running healthy. But I agree to an extend as I think that we also need to choose more actively to get better products. Each kind of action happens at a different level and they aren't mutually exclusive.
We the people have invented these authorities a long time ago precisely because we the people suck at making individual decisions to improve global outcomes, and we need to organize ourselves in institutions such as these to fix things.