These guys as you have admitted are doing a range of drugs at high doses, which is dangerous. Its good they understand the risk but that doesn't mean it should be legal.

As you have said there comes a point where your size and mass becomes a hurdle to your overall performance. My point is thats where we should stop then. Harmful drug use to raise that hurdle to another arbitrary high level isn't necessary. In other sports athletes reach that hurdle, where it becomes difficult to improve and they might feel the need to turn to doping.

The way they train now, without drugs would be damaging, again I'm not disagreeing with that. But by banning drugs you force athletes to change those damaging ways of training to train safely so that they are still healthy to compete. The ruined joints and ripped muscles you talk about are the result of poor training. Safe drug free training is preferable rather than forcing athletes to risk the affects of drugs to train harder just so they qualify to compete, and these drugs also have the affect of kidney failure, but also liver failure, stroke risk etc. Sure you can prolong their competing years but at risk of ruining their later years. This may be where regulated use of drugs can be a benefit to improve health rather than performance, but frankly if you train safely you don't need testosterone. Testosterone only allows you to reach a higher level of performance, which isn't needed if everyone agrees not to use it.

These people are taking a range of drugs at high levels, both of which is dangerous. With normal use steroids are usually fine but there is no safe steroid use at this level and they use a wide variety of steroids which aren't all 'safe'. I'm not sure what least harmful steroids you're thinking of? MGF? At the level they're using them the risk is all pretty much the same, sure you probably have a preference on whether you prefer kidney failure, liver failure, strokes etc. but the harm they're doing is happening now. Tests against doping will catch a wide range of harmful ones, which they will be taking now. They may use other harmful ones but at the level they're taking them they're all pretty harmful. In other sports, doping has improved the health of athletes, I don't think it should be controversial here.

I disagree with your claim that drug use makes it fairer, as I have pointed out before without drugs success is based on genetics + training. With drugs success is weighted on having good genetics + training + having some more good genetics (because not everyone reacts the same way or to the same extent from drugs, some may be able to handle a higher level of drug taking for example). By having a ban on most drugs you remove a barrier to entry and make it fairer, allowing those with a negative reaction to PEDs to compete too.

I do agree with you that regulated use may be the way to go to improve health, my argument however has been against the excessive use of drug taking to the detriment of health as it is now and that still hasn't changed.