Since you can only establish new chats using QR code when using chatmail relay, you can't actuall talk to the echo bot anymore. There's still a place for the echo bot in being able to test out your setup without involving others seeing your activity. We should consider that people that have just started out with Delta Chat may have anxiety around been seen to be using Delta Chat, and they may not want to jump straight into a group.

Bonus step later would be to build this automatically into the website as part of the onboarding docs.