My prior experience with some of the now leadership of Slack indicates that they don't have sufficient moral authority for this kind of commentary anyway.
I've been treated unethically by four relatively senior employees of Slack myself. It never occurred to me to complain until they started acting so holier than thou.
It's funny how achieving great success more as a result of luck than ingenuity seems to go hand-in-hand with arrogance.
Can you elaborate for those of us not in the loop?