US demands social media details from visa applicants

What is social media? Does it include HN, stackoverflow, my local railway fan forum? I have dozens of such accounts, it would be difficult to remember all of them.

Is the requirement limited to visas or does it apply to ESTA / visa waiver programs, too?

I have visited the US more than 10 times, mostly work-related. I hope I am never tempted to go there again. The Soviet Union is long history, but the US try to surpass it in depriving people their rights in many aspects.