This is a reasonable thing for MIT to do. Many comparisons to book burning have been made in various comments, which is not a good analogy. In this situation, the analogue to book burning would be burning his books[1]. MIT is just declining to have their name on the cover of his books (read: lectures) any more.

MIT is not trying to decree that the guy has some egregious objective moral failing. They're saying that they ran an internal investigation, with the help of other physics faculty, and found Lewin to be in violation of their institutional sexual harassment policies, and as a result, they're removing his content from their platform. This is a perfectly good reason to distance themselves from him, as well as making it clear that they take sexual harassment very seriously by impacting his legacy so negatively.

MIT OCW continues to host courses for 8.01 and 8.02, the courses his lectures covered, with lectures given by other faculty[2]. The loss of material to learn from is marginal at best - these videos are for the same courses at the same school with much of the same infrastructure (notes/recitation videos/etc).

[1] http://www.amazon.com/For-Love-Physics-Rainbow-Journey/dp/14...

[2] http://ocw.mit.edu/courses/physics/8-01-physics-i-fall-2003/