FB became big initially, because their privacy settings were strong. What is the guarantee that a new social network starts off strong on privacy settings etc,

FB became big initially, because their privacy settings were strong. What is the guarantee that a new social network starts off strong on privacy settings etc, will not become yet another FB as they grow big? (reminds me of Animal Farm). End of the day, I guess it is a business and every business just cares about their profits and keeping investors happy.