I don't disagree with you on principal, lateral, but the reality is that basically that's what careers do. How many guys working with concrete or chemicals of some sort are putting their long-term well-being at risk for immediate financial reward? How many guys taking uppers are there in executive jobs that almost never sleep who destroy their marriages by working long hours with poor hygiene/diets? And I haven't even touched off on the military or police or anything like that, to say nothing about football, like RM brought up. Hell, just playing hockey, basketball, football, soccer, running marathons, etc. all risk long term damage to joints, backs, brains, etc. even without PEDs or any other issues. The reality is that there is a certain element of health risk no matter what you do - some jobs come with more risks than others. Kids can absolutely play without risking their health. Does it lessen the chances they make it? Maybe. But that's no different than anybody else in any other field.
Why is one risk deemed not acceptable while others are? Hell, should we ban pitching above 50 mph in baseball because all these kids are risking TJ's surgery trying to make it?
Drinking too much water can kill you and that link actually even mentions how about 1 in 6 marathon runners develop hyponatremia - dilution of the blood caused by drinking too much water. Ban marathons, or ban excess drinking of water, or both?
I'm not exactly pro or anti-ban, specifically, but it's a pretty significant grey area for anyone to be making moral judgements in - especially when the rules change significantly part-way through somebody's career. And to suggest that this is something new is just plain wrong. Loads of guys from those historical records were juicing and experimenting to find new ways to juice. My personal favourite example was
Babe Ruth trying to inject himself with a concoction from sheep's testes - it didn't work, and actually made him sick, and the Yankees told the media he had a "bellyache" when he ultimately missed a game because of it.