I didn't like him, but he didn't deserve it in that exchange. The one that instigated should have been warned.
They both got temp-banned.
As for "should have been warned"...
...that's all a temp ban is: a warning. Our loudest, clearest, most sincere warning.
But, as usual, it doesn't matter how we do our jobs...someone will always come along to tell us how to do them better.