Ask HN: How would you react if someone in real life asked if you've heard of HN?
How would you react if someone in real life asked whether you've heard of this "obscure website" called Hacker News?
As long as you seem articulate, it seems like people won’t call your BS.
I also work at a YC company these days. HN is mentioned a lot at work. My username is really obvious to those who work with me. I try not to comment on HN threads trending at work, because my HN comment history is cringe.
On the twist side, most other friends don't know about HN. This is also the group of friends who ask "is Amazon a good place to work for tech?" The word hacker does put people off.