It makes absolutely no sense for rechat to be restricted. None.
Corporations, I swear...

Yeah, this is complete nonsense

+1 - No idea why this is removed in Helix. It's possible to log this in real-time, but I don't see how making historical chat data available to external parties is terrible. Even if it's just for the short time that the broadcast vod is available, I think a little bit of availability would go a long way in curbing ToS violations.

¯\_(ツ)_/¯

Twitch is restricting access to internal use only. It doesn't really make a lot of sense to me but they're doing it and at this point there's no stopping them. If you want the data, you'll need to scrape it. Is that incredibly annoying and highly inefficient? Absolutely. Will it support your use case? Probably not.

I see chat data as an incredible resource for the community to provide valuable insight on user interaction during streams. It helps everyone to know at what points the audience was highly engaged, and I have no faith Twitch is going to release a feature around this which actually serves the community anytime soon. Their clip system is a mess and they clearly don't know how to feed videos to users. Any content that isn't live needs to be shared through a third party.

YouTube is years ahead of Twitch on this, and they're catching up fast with live-streaming. To restrict data that would help the community and third-party developers make up for this difference is a losing move. Why watch a stream or VOD on Twitch when you can just watch the recap on YouTube? Maybe if Twitch made it easier to find moments of interest in multi-hour videos and view existing content on their own platform they could take some of this viewership back, but the changes in Helix show a prevailing theme - they intend to keep it locked down.

As of now the prod Twitch website still relies on the v5 endpoint that makes this possible when watching VODs will be removed -- how will Twitch even display VOD comments now? This needs to be addressed and supported for a number of third party content creation tools and the very website itself to function correctly.

I agree, removing access to collected data that is streamed publicly seems pointless. Why force developers to log this on their own? This is one of the most crucial data points for a livestreaming service and it's just being removed outright? Hopefully someone can explain the reasoning.

I don't understand why access to logged chat data is getting removed in Helix... There are still ways to collect this using the new API, but logging will need to be outsourced to third parties. Obviously Twitch will continue to log this internally, unless they actually plan to remove chat replay in VODs, which would be insane.