I'm not going to argue with you in general about the dangers of ketamine et al, I have seen it myself. But personally (this is anecdata) I have never had the compulsion to use it like so many others for some reason. Quasi-autism, a very strong internal governor limiting any compulsions , my NON-use of it as a substitute for cocaine like the majority of people... Drugs are only the tools for trying to manage whatever internal psychological processes are driving you to take them and if those processes are too 'strong', people go down the path you speak of. It is not the tool's fault, etc.
I was using K as a temporary vacation from reality aka k-hole. Lovely wonderful experiences and I innately knew it was helping with the depression. The most important factor was the set/setting/almost ritualistic use. And I don't do it anymore, never did it so much like so many other people.... and no compulsion to either. I have been sitting on some MXE for a decade now as well... I am an outlier??
Ritual is an element that is sorely lacking in the majority of westerner's use of psychedelics - it does comes with the ayahuasca package "just because that is what you're supposed to do" aka drugs tourism. But the other stuff... This element of ritual is what I think you're overlooking. Ritual also would have prevented DM Turner from taking ketamine before taking a bath which is a very really bad idea; he was really blatantly ignoring the risk factors for whatever reason.
This reminds me of a psychologist, Mexican I think, who in the 70s IIRC was using datura and other such things in his work helping patients. He's a bit obscure and I haven't found much info (I will hunt down my notes if people insist). So my opinion is that dissociatives have their use, but you really need to know what you are doing which most people do not. Personally, I think salvia is very useful... but I am sort of autistic and there is an Internet theory I came across that only the autistically inclined really take to salvia; neurotypicals can't handle the weirdness at some deep level. I have no proof of this but from what I've read and personally know, of course...
As an aside, I met Ann and Sasha a number of times 20 odd years ago. So I personally find it a bit irksome you're using such a handle. You've agreed to change it which I commend you for... For the newbies who know the name, but not that he's dead, it would be confusing. But you are relaying correct and valuable information, so that is good - except for the wide ranging generalizations ... ;)