40 requests every 5 minutes is a very small number of requests, and only a small number of channels on Twitch reach that size (and even then it’s usually only for hours, not 24/7), and only a smaller subset of those would great you the scopes to access their chatters list in the first place, so compared to the rate limit the number of requests is not significant.
Different endpoints, different scopes. A broadcaster may grant your app access to see their chatters list but they may not want you to be able to access their mod list. These changes have given broadcasters more granular control over what data they give apps access to.