Please make your substantive points without being snarky or aggressive. You have a good point in there at the end, but the site guidelines ask you not to comment like this, and that's especially important in Show or Launch threads.
Ok here is my less snarky and less aggressive take on the site and product: it doesn't leave me with confidence, it makes me feel uneasy about them as a company, it makes me not trust them, and it makes me feel like I'm being lied to. To fix this, provide proof. Otherwise, stop making the claims. Unfortunately with the frequency these kinds of products come out of YC, it seems like maybe YC coaches these companies as if this is an effective way to communicate.
The only coaching going on with Launch HNs is from me and tomhow, and I can tell you that we're constantly urging people to tone down grand claims, provide concrete examples, accessible demos, and so on—partly because it makes the posts more interesting, and partly to reduce surface area for the snarky and rigid objections that internet forums optimize for.
We don't do a perfect job of this, because (1) Launch HN coaching is on top of our main jobs running HN and we only have so many hours; and (2) startup founders' priority is working on their startup (as it should be!). They only have so many cycles for reworking everything to suit HN's preferences, which are idiosyncratic and at times curmudgeonly or cynical. Curmudgeons and cynics can't be convinced in the first place so it's not a good idea for a founder to put too much time into indulging them.
Some of what you're saying here boils down to that their home page shouldn't have any marketing tropes at all (e.g. testimonials, companies-using-us, etc.). I don't like those tropes either, but this is an example of what I mean by an idiosyncratic preference. Companies do that kind of thing because, obviously, it works. That's how the world is. The only thing that you accomplish by angrily blaming a startup founder for doing standard marketing is to make the discussion dyspeptic and offtopic. And yes, I do use the word "dyspeptic" too much :)
I mean, you can dismiss me by calling me a cynical curmudgeon (which is not inaccurate), but from my perspective their website doesn't try to convince -- it tries to bamboozle. I don't think it's idiosyncratic at all to expect that claims made should be proven and supported, and that companies should present themselves with integrity and be genuine in their representations.
> Curmudgeons and cynics can't be convinced in the first place so it's not a good idea for a founder to put too much time into indulging them.
I'd say we're just not convinced by marketing lingo and puffery. I was convinced by the simple README containing code and transparent evidence that a fellow HNer put up in their personal capacity, so maybe you can direct the Nia team to that as an example of how to properly convince curmudgeons and cynics.
i am interested in knowing what would be the correct way to do it according to your checklist. For example you said testimonial from twitter can be bots, which testimonial according to you would give you confidence that product is genuine?
Okay let's dissect it. First, I will say since this is a for-profit corporate website and they are trying to get something from me, I approach it with a fully skeptical, 0 benefit of doubt perspective.
What's the gif supposed to tell me? It's supposed to demo the product and give me a feel for its capabilities. But it just flits around and goes so fast, offers zero explanation for anything, it just leaves me disoriented. So at minimum, this needs captions and it needs to go about 2x slower. But really, this one GIF should not be the most substantive element on the first page relating to the actual product and what it does. Trust lowered.
Moving on to the "company carousel", which is trying to say "these other companies trust us so you should too". They're trying to ride on the reputations of Stanford, Cornell, Columbia, UPenn, Google, etc. as a sort of pseudo-endorsement, because they cannot post real endorsements from these institutions, because they do not exist (doesn't YC have legal counsel to tell them this is illegal?). How are engineers using Nia at Stanford? We don't know, Nia will not say, likely because no one at Stanford is using it in any real capacity that is impressive enough to put on the front page of the website. If they were, then why wouldn't Nia tell us about that rather than just flashing the Stanford logo? So the logo suffices, and I guess the more logos the better. Trust lowered.
Next the investor list: who is this for and what does it communicate? It appears to be a list of Chiefs, VPs, Co-Founders, and various funds who are deemed to be "world class", which is just another parade of logos but for a different audience, likely other investors who know these people. Maybe this speaks to some people in terms of the project having a solid financial backing but that's a smokescreen to distract you from the fact there's no actual business plan here aside from running on the VC treadmill and hoping to get acquired by one of your customers and/or investors. Trust lowered.
Then we get to the Twitter parade, which is a third instance of "just trust us bro". And it includes such gems as "Can confirm, coding agents go hard" and "go try Nia, go into debt if you have to". Testimonials are for products I can't try myself, this seems like something that can be demoed, so why isn't it? Why did they opt to devote all this space to show a bunch of random people saying random uninteresting things about their product, rather than use the space to say more interesting things about their product? Because the testimonials are a distraction from the actual product. Trust lowered.
Again, I'm left asking: Why do I have to listen to and trust these other people if the technology is so good? Why am I halfway down the page reading this thing, and I've yet to hear any specifics about how this thing works or what it does for me. I was told other people are using it but not how, I was told other people invested in it but not how much, and I was told some companies are maybe using it but not in what capacity.
So in summary, this page is: "Look how shiny! You trust us. No really, you can trust us! Seriously, look at all these people, who say you can trust us, you seriously can! Now give us money."
So to answer your question:
> what would be the correct way to do it according to your checklist.
Don't do any of the things that were done, and instead lead with the product. Prove all claims made. If a claim can't be proven don't make it. Stand behind your technology rather than testimonials.
https://news.ycombinator.com/newsguidelines.html