Definitely true. It's kind of like any physically intensive job that you can only keep up for so long before your body gets messed up to the point where you have to quit early. That "big money" isn't forever, it has to be saved up while it's earned for retirement later, which might be sooner rather than later due to physical disability.
Plus there's the lack of holidays, and in fact crazier work hours with fewer breaks and no days off during the holidays, because that's when there's the most shipping going on. Much harder than coding or other tech work in air conditioned rooms and breaks during holidays, etc.