There's definitely scope for doing more of that. But notice also that of the 200 students who also got that opportunity alongside him, 195 stopped attending those lectures after just a few weeks; we don't know about the other 4 but I'm guessing they didn't all change their life trajectories as a result. So you're looking for needles in haystacks, and if you do too much of it you're providing an experience that 95% of your audience concludes is a waste of their time.