At least he's not a skinny bottom bitch like the last Superman.
Reeve was excellent, I recall reading that he put on a lot of muscle for the role actually.
He wasn't ready to step on the stage of history and "do battle" but he wasn't exactly small either.
Nobody is saying Chris was small, he was a Huge dude, tall with big bone structure. No Michael Keaton.
What was said was, would it be viable with a Superman today (2013 and the current swole generation) with a similar physique on Reeves.
Compared to back then, almost every young man today is working out / consuming PEDs in every shape and form. It wouldn't be as impressive to that audience with a Reeves-physique, that's why they chose to beef up Henry Cavill i believe.
Reeves Superman will ALWAYS be THE Superman though. True Legend.