The guys who passed who "long-worked" for WWE didn't die as a result of working for WWE. The only case you can use is Owen Hart, and that was just a freak accident.
You can talk all you want about injuries and wear and tear... then you can look at a guy like Ric Flair who rarely missed time for anything even after his plane crash. Sure he spent a lot of time in a managerial role at certain points in his career, but when he spent several years at a time in the ring, he didn't stop again because of injury. There are guys who wrestled every single night of the year for more than a decade who never had more than bumps and bruises... then there are guys who fell victim to a freak accident, and that's of no fault to the company or the work schedule.
It's like suggesting that playing WR for the Indianapolis Colts is the most dangerous position to play in the entire NFL. They pass more than anyone, you take more hits than any other receiver and you're constantly in the middle and because your team is so successful, you're always scheduled to face the top defenses each year. But the fact of the matter is, Marvin Harrison spent a decade, 160 games, as one of the most durable WR's in the NFL and it wasn't until a freak accident occurred that his body began to let him down. Reggie Wayne is still one of the most durable WR's in the entire NFL and he's been thrown to over the middle as much as anyone and absorbed as much contact as anyone.
All it comes down to is how lucky you are to avoid the accidents. As far as all these guys needing pain killers to get by every day... I say look at CM Punk and where that man is. He's going to be in a lot of pain one of these days because that's just the way athletes end up, but he says frequently that he feels perfectly fine 90% of the time... and it's mostly due to the fact that he's been lucky enough to not fall victim to freak injury after freak injury so far in his career.
