And yet HF is used in dentistry, for example. Recently had some work done and the dentist used HF to etch the tooth before cementing in the new inlay. Of course that was only some <10% HF gel product. (I remembered enough about concentrated HF from my undergrad chemistry studies that I asked whether it was a good idea to put that stuff in my mouth and he then explained it’s just a diluted gel.)
That would make me nervous also. But, there are so many substances that are incredibly dangerous when concentrated but incredibly useful when diluted. We had a saying in HAZMAT, “The solution to pollution is dilution.” There are some substances which are still dangerous in very low concentrations, but most are not.
The police officer who collapsed and almost died in the article the thread is about was trying to rub a very concentrated substance from his uniform. If it had been a concentration of 10% of the very same substance, he most likely would have had no noticeable effects at all.