There are good reasons not to dogfood critical services like that; it can make recovering from unexpected issues much harder if you introduce mutual dependencie

There are good reasons not to dogfood critical services like that; it can make recovering from unexpected issues much harder if you introduce mutual dependencies. For example, if Slack devops team were to exclusively communicate over Slack, then a Slack outage would be much harder to resolve because the team trying to fix it would be unable to communicate.