Here are your real measurements.
Official player heights are supposed to be without shoes (which is how Royce went from 6' 6" to 6' 4", Donovan went from 6' 3" to 6' 1", etc).
The point here is size on the margins is kinda relevant but quite overrated in terms of importance.
Don't ask me why Conley is listed at 6' 1" on NBA.com when he is 5' 11" w/o shoes, while Mitchell is listed at 6' 1" when he's 6' 1.25" w/o shoes and 6' 3" in shoes. On that note, people need to not perceive them as the same size; Donovan is two full inches taller, has a wingspan four full inches wider, and is
40 pounds heavier than Conley (saying nothing of the difference in explosion). Mitchell doesn't have awesome size for a SG, but he's really not that undersized if undersized at all when you take everything into consideration.