I dont think you are realizing what i wrote above. Perhaps go up and referrence.
Basically it is about the taboo on studying this kind of thing amongst the majority and that has influence on scientific study. I am not saying there are or arent many subspecies of modern day humans. What i am saying saying is the rank of subspecies is more well defined and accurate and humans have a lot of variation which is obvious and consistent within certain groups (especially geographical).
As with the medicine point, there are valid reasons to accept this fact and study it. I dont study humans so not going to tey and make it a thing. But have been breeding and hybridizing animals and plants for 20 years and going out on field studies to study wild populations. So am a little bit familiar with characters, reproductive possibilities and line breeding etc. Its very clear humans have incredibly unique and diatinguising features that in any other case would classify them into sub species or varieties. The thing with subspecies is that its slightly more well defined and “concrete” than say race or any of the even lower ranks in plants.
See the link to a psychology article posted above talking about this very point of not studying sensitive topics. Yes we are aware there are a few that do. Also aware there are many who avoid it.
For those reading and not getting the context of this thread it started here talking about chinese claiming english and evolution of languages etc.