Amphetamines were used by lots of ball players (and regular folk) back then. Mantle and Hank Aaron also used them. They aren't performance enhancing in the same way the stuff the dudes in the 90s were using. Hell, they aren't even as enhancing as the coke many ball players used in the 80s was.
So it's not the intent behind the cheating, it's the effectiveness that counts?
it's not the only thing that "counts", but yes, how effective it is plays a part. If a felon is in possession of a weapon, should her sentencing be different if she has pepper spray vs an AR15? Should the speeder that is 5 over the limit be treated the same as the speeder that is 75 over?
I don't think that analogy works, because it's not like the amphetamine users had access to steroids but didn't use them to cheat less. And even if you come up with a better one (my car can only go up to 75 mph and yours can only get to 80, and we both drive at maximum speed in a 65?), I'm still not sure that comparing to actual crimes really works, because cheating at baseball just isn't comparable to breaking laws.
Maybe the best analogy is that you pocket a couple extra $500 bills in Monopoly, and decades later I play a newer edition of Monopoly that has $1,000 bills and I pocket a couple of those.