I would say Cryptography and Compilers are among the best courses on Coursera (I can't speak for your other examples) and are not representative. The fact remains that even the best Coursera courses are not comparable to the education you would receive from similar courses taken on campus. One important reasons for that is the multiple choice or final answer quiz format is far inferior to long answer. For example, questions of the form "prove that" or "show that" which are staples of a rigorous course are essentially non-existent on Coursera for practical reasons. That would be fine if Coursera had somehow improved, in terms of learning quality, on that method of assessment but they have done the opposite.