from memory:
Basically, Udemy monetized his content–python lectures. When he complained, he was told that in order for Udemy to stop, he would have to
a) join udemy (in order to actually view the videos behind the paywall, and thus submit a valid DMCA takedown)
b) accept the licensing terms that udemy imposed.
c) realize that the terms meant that he would not get paid, should udemy decide to promote his content with discounted offers, advertising, etc.
