You can then create a function to retrieve the necessary data from the members’ database, it’s generally better to have your data stored privately and securely, and only expose the necessary data depending on the situation, than having your data exposed by default, and make you look for ways to secure it.
If users don’t know whether their data is private or publicly exposed, they’ll sure hope it’s private.
Also, even in case of someone wants to build a social media network, do you think that social media networks like Twitter, Facebook, Instagram, etc… have their databases publicly exposed? If that’s true, you should be able to get a list of millions of users.