That's fine for some people, but most people don't have a real world WOT to trade bitcoin because there aren't that many bitcoiners, specially if you are a normie, you want something simple, just an app that allows you to sell as fast as possible without much interaction, I won't be able to tell a normie or a business owner to go to an app an meet in person with someone and receive cash in handled. They just want to be able to swap bitcoin that they might earn to fiat in a simple way, the simplest way could be an exchange but they can get blocked.