> Your logic doesn’t make sense to me. Pre-digital, a book could just be shared with a friend one at a time (unless you wanted to xerox the whole thing which I’ve seen but it’s always low quality).

Sure, but books also had a much higher value due to a relative lack of competitors. Books now have to compete with a plethora of free media available on YouTube, forums, blogs, etc.

Some of them may be of lower quality, but it's hard to beat free. Lots of us have taught ourselves skills via free resources that we probably would have had to pay for at one point.

It's much harder to charge for knowledge than it once was.