Generally when people start having a back and forth about a product I assume it’s astroturfing unless it makes sense in context and/or it’s just one of those brands people genuinely get excited about (they tend to be obvious ones you’ve seen a lot already).
Doesn’t mean I don’t ever get duped, but idk. You learn to spot the signs. I imagine most of us on HN catch most instances. Genuine-seeming referrals aren’t as easy to fake as one would think.