I like the name “Learner’s Mode”. This seems like something that could be implemented as a Theme, or a set of Themes, which could be made available in the Theme Switcher.
If the Discourse Forum Helper AI Helper is enabled on a Discourse site (like it is on this site), then users (all users, since we are all Learners here, always learning something new!) can select any text and get at least some instant edification, like so…