You also have to praise and reward devs for their successes. It's not black and white - you don't have to pick between banter OR praise. You can have both. It's a dynamic. Show them that you care and that they're doing good work, genuinely. Tease them about small mistakes with tools like this, sarcastically and socially, and it helps build up rapport and make the team that much more tightly knit. Pointing out simple mistakes in a tongue in cheek manner is a good way to show someone that they've made a mistake, but it's not a big deal and no one is actually upset with them about it.
It's still difficult to know when the line has been crossed. What's perceived as harmless (even productive) banter by everyone else may still be hurtful to the recipient. You never know whether someone is okay with it, or simply hiding their emotions well.
I do agree that a copious amount of praise goes a long way toward developing a healthy environment.
