Funnily enough, from Slack's own testing they could make it that tool tomorrow by changing the input box from a single line to a multi-line input. A la the Hacker News input box we are all typing into right now.

You got me thinking about whether a pre-send message that could theoretically appear: "Given the channel that you are currently in, this might not be an appropriate message. Would you like to reword it, have AI reword it, or send it anyways?"

This presumably would feel absolutely terrible to use, but it might be a way to nudge towards community consensus for how certain spaces would work.

No one is claiming that level of productivity.