These questions are almost impossible for some of us to answer completely. I own entire domains of email addresses and make them up on the fly, I've also thrown away dozens of "social media" accounts in the last five years for trivial reasons.
That's why this initiative in nonsensical. They'll never know whether the answers to these questions are complete and accurate. I'm pretty sure that later tonight, a new paragraph will go into the ISIS handbook saying "create a Facebook account in your real name that you can give to the authorities, that has nothing on it except for pro-American content". That would actually be good advice for all prospective travelers to the US. Lock down your real profile before your trip so that it can't be searched for, and maintain a separate, public, very vanilla profile that you can give to them. That's all it would take for most people to go through with no issues.