I have just read the blog post Iterating on Inclusion by Sara Chipps about all the recent changes SE made to improve the site experience. These are all great ideas but they have one single common downside: they don't teach users how to get better.
You write that:
For some time, we’ve been using machine learning to flag comments that might be potentially troublesome in the community, especially if they could be seen as hostile to new users. (Our tool for evaluating and flagging those comments, called the Unfriendly Comment Classifier, is pretty great! We’ve got details on how it works here.)
(emphasis is mine)
It would be great if you didn't just flag them but notified the user about the fact that it might be potentially troublesome in the community and gave them at least a chance to fix it before it's too late. When someone gets flagged a couple of times and earns a timeout - they might not even know what it was for so there is still a risk that they will repeat this behaviour unwillingly in future.
Additionally there should also be a link to a page explaining how to write good comments. I highly doubt that all bad comments are bad because the authors had bad intentions.
From my experience there are a lot of people who do not know how to communicate or use diplomatic language and they might be flagged even if writing in good faith.
You can help people learn by expanding the comment's help
or even providing examples of good and bad comments. The current dropdown only explains what comments are for, and how to format them, with a link to the page Help Center > Privileges > Comment everywhere - which is all very technical guidance about formatting.
I find there should be much more teaching than secret flagging and penalizing. You should show people exactly which comment was bad and why. Don't leave them in the dark. I'm pretty sure most comments are written in good faith, maybe sometimes too emotional but still, I doubt they were written with the purpose to offend anyone.
The current system disciplines users by punishment. In my opinion this is not inclusive at all. The system should support us and teach us how to use it correctly while we are using it and not kick anyone out when this could have been prevented.
You now have the Unfriendly Comment Classifier
. Use it proactively to protect not only readers from being offended by inappropriate comments but also their authors from being flagged.
Teaching could also be supported by moderators telling users why a particular comment was removed -- similar to the feedback that shows why a question got closed -- maybe providing some predefined reasons. Just saying, rude or abusive is too general. People have different standards and many users don't speak English as a native language, so they might not even know something was perceived as rude. We have the chance to learn how to write good questions but we're completely lost when it comes to the comment world.