Sunday morning is also a lull time for most. That said, there is more traction than I expected. That that said, bibinmohan made that followup comment about 18 minutes after posting the AskHN.
HN opinions are not representative of the general population.
There's definitely an echo chamber here, and as long as we recognize that and not think opinions here are normative, we can appropriately discount very emotional and contrarian opinions.
I use FB and so do many of my friends. Why? We're all older and people like posting pictures of their kids. It's also a lot less intrusive.
I'm sure we've all been at dinner parties where someone wants to show you your photo album and you have to pretend to be interested but it's a chore. FB lets them show their photo album in a way that is passive, and if something catches your eye, and you can comment but otherwise you don't have to engage. Win-win.
I unfollow or block friends that post politics or other stupid stuff. It keeps my feed fairly clean, and I get to see what my friends are doing. When I meet up with them, I have context for starting a conversation that is less surface level.
I think better answer would be it is no longer cool to have Facebook account specifically for people on HN. So even if we have account we would not come and accept.
I have an account that I have not logged into for 10 years - I do not think that really counts.
It doesn't help that you asked the question in the middle of the weekend night.