If you take testosterone injections, it's not that unhealthy as long as it's not crazy doses. Arnold definitely fell way back at a younger age. I'm sure he still takes injections (you pretty much have to keep it going forever once you start) but the steroid abuse wasn't as bad in his day as it is now. Once he got out of bodybuilding and into films, he would go on to deflate considerably by the 90's. Also, there's a lot of new science suggesting that even a 1 month cycle of testosterone can have permanent ability for you to gain lean muscle mass more easily. There are also so many kinds of steroids. Pure testosterone (which is mostly what they had back in Arnold's lifting prime) is less dangerous than some of the stuff that's out there now. Arnold never took as much stuff as someone like Ronnie Coleman (feel free to google him; it's crazy), and he didn't have access to the crazy shyt that Ronnie and people now are able to take, so Arnold avoided ruining himself and his health.
Regarding The Rock, I'm more worried about his long term health, because he's almost 50 and he's clearly doing some pretty heavy stacks. For Pain and Gain he got way bigger than he'd ever been as a pro wrestler. The good thing The Rock has going for him is a fukk ton of money to pay for the highest levels of science and knowledge to help him juice as intelligently as possible. I guarantee he's got a team that helps him, does blood work all the time, and helps him adjust his stacks and his cycles. He also is probably able to take the highest quality stuff.
Absolutely. Yeah, once you're on gear, you're probably on it (especially at lower doses) for life. The biggest reason I never tried it is I was terrified of having to be on it forever.
What was his last R film? Doom maybe? Or am I forgetting something 
and most actors looking at how much money they gonna get it’s like 
since when?