Truth is, sure, people, to varying degrees, can develop muscle without drugs and extra hormones. Some can build quite a lot. But to acquire a physique such as the kind (and conditioning/tightness) Vince sported during his competitive days absolutely demands the use of these things. Undoubtably an individual has to also possess a certain combination of genetic traits to reap the rewards of such use that results in a pro-caliber physique; but in a very real sense, the drugs, etc., are the "key".
Taylor's training would never have built the man much of anything bodybuilding-worthy had he not been using large amounts of drugs and hormones. Fact. He would have been a muscular but small guy.
A true muscle man has dense muscle and great strength, even without drugs.
Vince has neither.