It's also ethically fair game to base your decisions to launch a product on the amount of consumer interest the category gets. Everyone does that.
What they promise not to do is take a look at seller specific data. That makes sense because it won't get them much extra compared to looking at categories, and the sellers ethically claim it's their data.
Actually - as the article described, they DO spend a lot of time looking at SPECIFIC seller data for unique products because it gives them LOTS extra that category details don't provide.
Could you please stop using allcaps like this? This is in the site guidelines: Please don't use uppercase for emphasis. If you want to emphasize a word or phrase, put asterisks around it and it will get italicized.https://news.ycombinator.com/newsguidelines.html.
What they promise not to do is take a look at seller specific data. That makes sense because it won't get them much extra compared to looking at categories, and the sellers ethically claim it's their data.