Twitch should start gatekeeping stream tags.
Lately there have been too many streamers misrepresenting their content with incorrect tags, using them only because the tags are popular and bring them more attention. These are streamers who ALREADY hold 99% of the viewership on Twitch, and they don't need to be stealing it from communities where they don't belong. This is unacceptable and I believe there need to be penalties for such actions.
Since Twitch refuses to suspend/ban their cash cows though, I propose an alternative solution. Implement a way to gatekeep them from using the tags. If they've been reported and investigated for tag misrepresentation and found to be in violation, Twitch staff should be able to disable their access to the tag(s) in question so they can't add it onto their streams.
This would solve the problem, AND you get to keep your big streamers who make all your ad revenue or whatever. You have no more excuses. Make it happen, Twitch.
I think you can report such badly categorized channels, and then forget the whole thing. Don't expect, that Twitch will do anything regarding this. :)