It just makes me so sad that I discovered HN so late !

That thread was unbelievable, man hackernews discussions were very enlightening back then, drew houston even introduced his startup in that thread.

I hear you. But just wait. You've already been on HN for four years. I remember discovering reddit, and then HN, and thinking similarly to you: "whoa, wouldn't it have been cool to have found this earlier?" And yes, it would've been cool. But hey, you found HN. You could've found it later. In a few years, people will be telling you how awesome it is that you found HN so early.

Similarly, I started going to Improv Everywhere events in 2006 (https://improveverywhere.com/2006/02/18/cell-phone-symphony/), just before they stopped doing every event as a massive cattle call. I was disappointed that I found it so late! But a few years ago, on a reddit AMA, the founder of Improv Everywhere himself told me that as a "longtime attendee", I should make the point of saying hi to him the next one I went to.

So wait! Be happy you didn't find it later, and think about how much history you have to discover.