Nonsense.
Just off the top of my head I can think of several successful MLB pitchers with a history of chronic injury
Chris Carpenter (5 arm surgeries)
Jack Flaherty (multiple trips to the IL with arm problems)
Adam Wainwright had multiple arm problems over his long career.
Jacob DeGrom
Chris Sale
I could come up with more if I wanted to.
Pitchers have injuries. Throwing a baseball over a long period of time is not normal behavior.