I appeciate short letters like this that get straight to the point...
I have watched it happen multiple times that someone from academia joins a research group at a large corporation and finds out to their chagrin that they can't just overtly bully colleagues as easily without tenure.
edit: And it looks like Mitchell immediately left an angry comment about being called a "linguist" despite the article never doing so. Starting to notice a pattern of confrontation, ego, and escalation among some of these people.