I don't see how it is wrong as a maxim. Sure there are cases where the products don't turn on the users because they are sustainable or have received enough fun

I don't see how it is wrong as a maxim. Sure there are cases where the products don't turn on the users because they are sustainable or have received enough funding/backing to last for a while before having to seek for alternative forms of monetization, but otherwise we know operational costs for products need to be met somehow, and the way to do this while still having a broad consumer base is to not charge the customer directly but to profit off of them by selling data or inferences drawn from said data.