Most new founders think that blasting your 'startup' to Product Hunt, Hacker News, Indie Hackers, Reddit, Twitter, etc. will result in first customers -- that that's 'marketing' -- but that's far from the truth for the majority of products. And contrary to popular belief, the chances your product is one of the exceptions is near-zero.
Those social media platforms bring in 'tire-kickers' and devs that value their time at $0, not customers. These aren't the first users that you should be listening to, because they will always complain about price, lack of niche functionality, etc., yet it's pointless to listen to them -- because they aren't buyers.
You want to market towards buyers, not just users, and ads are a good way to do that for early companies that have no brand awareness or distribution.
For me personally PH would be more like ideas to copy from.
Hence the importance of industry knowledge and gut feeling.
Entrepreneurship is not for weak hearts.