Indeed, could all go in circles pointlessly with opinions that we dont really have enough basis for in terms of proper clinical trials, even though of us who think we know someone strongle effected or not effected, people are notoriously bad at diagnosing changes in their own mental health anyway.
Even people with very severe cases of schizophrenia and illnesses like that for example genuinely believe they are NOT suffering from anything so spotting a very mild change in attitude is almost impossible for the drug abuser.

I will say though that Im not aware of ANY clinically prescribed mind altering drug on sale which is without documented long term side effects from long term use, so it seems unlikely to me that E would be the exception to this.