Later it became "Hacker News" and the focus seemed to largely stay mostly the same for a long time, with a slight widening of focus to include maybe more general science / tech stuff, not just stuff related to startups.
Over time, the focus has broadened even more to where some of the early stuff is pretty de-emphasized (you don't see as much fundraising advice now, for example) and you get a lot more general news, politics, world events, etc.
What's "on topic" is described pretty broadly in the guidelines[1] as "anything that gratifies one's intellectual curiosity."
OTOH, the guidelines also say "Off-Topic: Most stories about politics, or crime, or sports, unless they're evidence of some interesting new phenomenon. Videos of pratfalls or disasters, or cute animal pictures. If they'd cover it on TV news, it's probably off-topic."
But yet we still get a fair amount of political content here, and more than a little bit of stuff that probably is covered on TV news. But we still manage to avoid "cute animal picture" and generic reddit/4chan style memes and shit at least.
The site is a discussion forum aimed at tech people and potential entrepreneurs. It is part of the business model for YC in that (last I checked) you needed a handle here to apply to YC, a start-up incubator that provides seed money and all kinds of education and what not for nascent companies wanting to hit it big who have the potential to be the next AirBnB. YC is, in fact, where AirBnB got its start.
Last stats I saw: It is predominantly male, sometimes thought to be as much as 97% male, though I think that is probably an exaggeration, and the bulk of the members are mostly in their 20s and 30s, though ages range from early childhood to at least 80s, last time I saw an onsite survey.
The intent is to discuss things that are intellectually engaging. It has a few other aspects, like Show HN, that support the general interest in supporting web-based businesses just starting out.
I suggest you look around, do some reading and not jump to conclusions about people replying to you.
Edit: YC is short for Y-Combinator, if you want to google the name of the incubator and get additional info. I don't seem to have spelled that out at any point, though I had intended to do so.
I've even upvoted your question.