Hopkin runs a 4.41 (really fast) compared to Calloway who runs a 4.57 for comparison that is slower Treylon Burks and Michael Thomas. So last year when he couldn't separate, now you know why.
Every combine source has him at a 4.57/4.5. Combine Results. Go watch Deebo Samuel, Justin Jefferson, or OBJ (who all were given faster 40 times) and say he's faster than any of them. He obviously doesn't run a 4.41.