> Isn't that the complete opposite to what teaching is about?
You can lead a horse to water, but you can't make it drink.
I taught EFL at a high school for 5 years. Being a good teacher takes a lot of experience, inspiration and hard work. It is a very, very difficult job. When I was doing it, I often thought how much easier it is to explain things to a computer compared to a person -- especially when the person is often doing everything they can to avoid listening to you ;-)
I don't want to diminish the role of a teacher because there is a huge difference between a good teacher and a bad teacher. It's just that there comes a point where you have to realise that the best you can do is to create an environment where it is possible for the students to learn. Everything else is up to the student.
The OP's point is very correct that of students who succeed, the vast majority would have succeeded even without the teacher. In those cases, the teacher may create a more pleasant environment, or may provide a convenient filtering of information. But there are very few disciplines where a good text book and a place to practice aren't enough. Where foreign languages are concerned, you don't even need the text book!
I fairly quickly realised that my "value add" in the classroom was to help those people who were borderline. There are always some people who are eager to work, but are constantly at a loss about how to start. In my experience, this is a very small percentage of the class (maybe only 10%), but you can make a big difference as a teacher to these students.
The real problem is where the teacher is placed in an environment where they are unable to concentrate on those students. For example, I often had classes of 42 students. For a language class, that's horrible. I can actually manage with 20, but if you get up over 30, it becomes impossible to spend enough time with the people who need it.
Of course, just like high school (which is filled with students who don't want to be there), undergraduate courses have massive numbers of students who are hopelessly uninterested in studying. There was a time when "university" was aimed at a very small number of very keen students. You had lectures with less than 10 other students and had tutors who helped you work your way through the ridiculously large amount of material that you had to learn. But such organisations are never going to fund a proper football programme, and what is the poor NFL going to do to train their players? ;-)
I mean your point is completely fair: society should take its share of the blame. However, consider who makes up society? The very people who think it is completely reasonable to drift from high school to university, take a bunch of random courses, and party every day. These same people whose career plans are to take their gold stamp for having sat through 4 years of boring lectures and exchange it for a "good job" (TM), which will bring them a very high salary but will have completely unspecified content.
Although, contrary to my rant, one of the things I really like about code boot camps is that it allows people to "wake up" from their delusion. After getting a general degree in "business" with specialisation in making unnecessarily complicated Excel spreadsheets, and working as a drone in the financial industry for 2 years, suddenly some people think, "OMG! Programming is amazing. What the heck have I been doing with my life?". Some of the best people I've worked with recently have come a similar route.
So it would be extremely great if we could help society get over this expectation of mediocrity and start making universities that are centres of higher learning. However, a teacher in a classroom is up to their ears wrestling with extremely unfortunate social dynamics and doesn't have very much time to change the world.