You don’t have to worry about that at all as Sony has revealed at GDC that real name IDs will be optional. PS4 players will have their real name ID and their normal PSN ID. They can choose which one is displayed for the world to see.
So you won’t have to link your Facebook account to your PS4 online profile either it seems.
This will probably make a lot of people happy, myself included. As much as I’d like to see the many trolls of online gaming get what’s coming to them I don’t think forcing players to use their real names online is the answer.