You're missing the value-prop of Grammarly -- to help someone who doesn't know write more like a fluent native English speaker. Helping someone write "more average" is exactly the point until they're fluent enough to know when and how to break the rules.
Wait until you find out about the 5 paragraph essay that's taught in HS that follows this model.
Wait until you find out about the 5 paragraph essay that's taught in HS that follows this model.