i would be curious to know how long a pitchers career lasted in those days.
Most didnt last as long as many think, and for the ones that lasted, they did stuff that is not allowed these days. Reality is that most pitchers average time in ML is 4 years, for the few hundred that do make it hundreds did not. The difference was the injury factor.
One of my sons pitching coaches (2 seasons in pro ball) was Dennis Martinez, a recovering alcoholic always stressed with the pitchers how important it was to come clean if you had issues. There is only so much anti inflammatory meds a person can take before their stomach blows up.
FWIW, I know of a few guys who actually became drug dependent due to arm issues, actually recovering drug addicts. They chose to take strong pain relieving drugs because they knew that any major injury would put them way behind.