You've missed my point or didn't read it. This is not about the market fitness of the idea/product. This is about the parent commenter throwing shade on the inventor's curiosity and aspiring entrepreneurial effort. Regardless about how right you or the parent is about the products fitness, making assumptions about the inventor's motive removes the opportunity for the inventor to learn/grow from their attempt at going to market.
Instead, it would be better to support the inventor with constructive criticism... how they might better measure PMF, how they might prove whether there's a need for their idea in the market earlier, or how they might get more efficiency out of their approach.
And if you don't have the criticism to offer, you can probably find a better way to share your knowledge without saying the idea is terrible or they are acting in bad faith. (Or just don't comment at all!)
Instead, it would be better to support the inventor with constructive criticism... how they might better measure PMF, how they might prove whether there's a need for their idea in the market earlier, or how they might get more efficiency out of their approach.
And if you don't have the criticism to offer, you can probably find a better way to share your knowledge without saying the idea is terrible or they are acting in bad faith. (Or just don't comment at all!)