We have a method for peer-to-peer transactions, it's called the fiat system (paper money). Bitcoin's main use-case is censorship resistance, this means that the government cannot freeze or seize your account, and if you keep your public address away from the public, no one except the person paying you will know that the wallet belongs to you.

Even when the lightning network is running flawlessly, and bitcoin transactions become instant and free, will you risk paying retailers with it?