This has been developing in martial arts for many years. I don't think it's necessarily the fault of instructors or schools but prospective students or new people seeking to learn martial arts. They (the new or possible new students) seek to learn self defense or a martial art but many of them are turned off by the idea that they may and will get hit from time to time in class whether it's from sparring or whatever. They want to essentially learn how to be street warriors (or someone who just wants to be able to take care of themselves out on the street) but they don't in any way want to do the things it takes to become that warrior. So there's a disconnect in what they want, their expectations of what it takes to get there and what they're willing to undergo in that process. Medical and dental work is expensive so I'm sure that plays a role as very few want to lose teeth, break a nose or get serious bruises and sprains on a regular basis but I'm sure school owners/instructors have had a harder time getting a keeping students in the striking arts than some other arts. While BJJ is a great method to learn and ppl do get hurt, it doesn't look as visually intimidating as maybe Shotokan Karate, or TSD because new practitioners typically don't see strikes so it's easier for them mentally to tell themselves they can do that and further that they want to study it because it's effective. But what they don't see is what is the alternative... For example watching a pro mma fight where one fighter is skilled in all around techniques going up against a strict BJJ practioner who throws no punches nor kicks. Without offensive striking weapons on the street, you'll lack the most effective thing you have which is to quickly cause pain, discomfort or unconsciousness in that aggressor. Instructors have to find a way to just tell the truth to new students in the striking arts and find a way to bring students along in the process to overcome the fear and to protect them as much as possible. There are going to be those potential new students who will in no way voluntarily seriously spar, get hit, give hits and keep coming back to class so there is no way to realistically serve those students in the striking arts in my opinion.