Turbo helps creators indirectly. whenever adds play, it gets automatically counted as a view to advertisers and documented in the account revenue breakdown. IMO: to a Bargain hunter, twitch turbo is a better value. add free site wide for the price of 3 channel subs.
For some people, its the emotes that are the main selling point to channel subs. That's not my thing, but I do notice it when I don't have a channel sub when its not gifted to me.
To a small Twitch streamer like me, I push the Twitch turbo. I don't have many emotes on offer and when I raid out to friends and stream teammates, the ad revenue helps them. At the same time, as a streamer, I dont want to wait on ads for a raid target.