If all you're going to look at is height and weight, then I can't take you seriously as an evaluator. Production matters. Eli Morgan was the most productive pitcher in our minor league system last year. If he can even become an occasional spot starter that bounces between AAA and the majors with mixed results, there's value in that depth. Not every guy needs to turn into Bieber.
If you want to point to the actual red flags like his increased walk rate in AA, or that as an extreme fly ball pitcher, he's unlikely to maintain his low HR/FB%, go for it. However, ruling guys out based on their stature is outdated.
I'm not betting on Morgan to become anything more than a depth guy, but he has a ceiling higher than that. There's certainly no reason to trade him unless it's as part of a package for immediate MLB help.