E-mail verification is already a thing, the image there is a mock-up for just the chat list options ( https://www.twitch.tv/settings/channel and scroll down) , here is the actual settings screen for that section: https://srink.net/2PXgU1n
Regarding the other points:
- Just because the API roadmap has it there doesn’t mean it’s a feature change on the frontend side of things, and more than likely we won’t see a change just because they add an API endpoint. I say this because the frontend chat list hasn’t really changed since JTV.
- While client side filtering is always an option, it doesn’t address the concern of many broadcasters, which is that they appear in the list at all and can be seen by them and other chatters/viewers. While this wouldn’t do anything when it comes to third-party chat apps (chatty, mIRC) it will improve the view on Twitch.
- There is already server side filtering for chat related features that broadcasters can enable/disable (auto-mod being the biggest example of this), why not add one for the chat list? Default to enabled and display all, if they want to change it they can. While this does require a rework of the frontend display of the chat list, that’s something that needs to happen anyway.
- You made the exact point arguing for this, by filtering non-active chatters they don’t appear in the list and thus lose out on being seen by others. It also allows for a “is_active_chatter” flag to be set that can then be used for channel specific giveaways, gift subs, etc… It adds an option for future things to be done with it.