Zooming way out, it is a nice experience to be able to contact someone to clarify a possible misunderstanding.
On the other hand, how many “misunderstandings” result in a permaban?
This is not an official Discourse answer, just my personal experience from running half a dozen community sites of smallish size: there are plenty of fish in the sea, and it is okay to ban the ones that make your forums a bad experience for the other users. 