Meta is only network effects. You could build that in a weekend, and so could I. or you could just fork Mastodon. What keeps people from leaving is that their friends are still on it: network effects
The curious thing about that is the transformation of the feed — it’s long since stopped being majority friend/follow posts and clearly is the algorithm picking whatever else it can come up with that will engage. This should mean personal network effects aren’t the moat anymore, for FB anyway.
I feel like making a system capable of delivering the amount of data that WhatsApp/instagram deliver to billions of people worldwide would take more than a weekend.