The ad hominem was "doesn't get HN in the first place". It's very dismissive of people who disagree with you. And it's not the first time you've responded like this.
Oh, I see now. Sorry about that. Normally I'd delete it, but in this case I suppose I'd better leave it in.
I still don't see any ad hominem, and as a statement of HN's very specific values it seems obvious to me, but you're right that I shouldn't have said it in a dismissive way.
I don't get it? No, you don't get it.