The ban on altitude tents seems stupid to me though.
AFAIK they (tents/chambers) aren't banned universally - not by WADA at least. I suppose the thinking goes that it's a passive way to gain advantage and training should be active, and miserable. If that is indeed the argument (I'm guessing) it does seem a bit reminiscent of some of the restrictions from the days of amateurism when just taking things seriously was seen as a potential form of cheating.
As to weight loss drugs, it's interesting. They may not be
directly performance enhancing, but they are prescription drugs with specific therapeutic uses. Taking them purely for the purposes of sport does seem iffy and raises the possibility of competitors being pressured to toke them outside of their proper medical context which could be dangerous and/or unethical.
Mind you, BITD when I first heard of autologous blood doping it seemed to me to be a natural, if somewhat extreme, thing to do. But then I hadn't really given it much thought.