Earlier quoted context omitted.
What if your product is good and you want people to purchase it? Why not let the customers decide what is good and bad - they have agency.
The point of marketing is to remove and subvert that agency, disconnect buying decisions from real value, and to limit the consequences of flaws and underperformance.
If I'm shown an advertisement for a watch from a well known company with some detailed specs I'm inclined to believe it based on the brand reputation. This signal (the specifications) is valuable to me but not necessarily completely accurate. I'm better off with the signal than without. The reason being there are more instances of truth than lies across all advertisements.. otherwise they wouldn't work.