Of course he has. From 45 / 50 age, it's very hard to lift weights naturally. A treatment is almost a necessity (libido, energy, quality of sleep, skin texture, reflexes, brain function, etc). Arnold can afford the best doctors and products.
Biceps become very fragile from the age of 40. My father broke one of his biceps with a wheelbarrow. So I am very careful: no sudden movements, no mixed grip during deadlift, a good warmup, very very light stretching, no barbell curl (only dumbell). I think the best way to keep the biceps in shape, is a relatively light training (10/15 reps). They respond well to the pump. Also, try to keep the shoulders and forearms healthy. Otherwise biceps try to compensate and tend to break.
its not the bicep muscle that becomes fragile. More so it's the proximal bicep tendon and more commonly the long head which is prone to "break" snap or tear as one ages usually secondary to arthritic conditions of the shoulder joint or rotator cuff problems. If the surface of the bone the tendon glides upon becomes rough it grates the tendon until it snaps. Like a mountain climbers rope rubbing on rough rock. Certain shoulder impingement syndromes can cause this too. It's not typically the heavy lifting that tears the healthy bicep but rather the tendon is frayed n the person doesn't now it. It's on its way to snapping n one day it just goes wether lifting heavy or not. Granted a guy with a desk job that never does anything heavy prolly is less likely to snap a bicep tendon though.