as explained in the interview, the course changed to python because the course itself changed. they basically killed off the old course and created new courses built around their new degree program structure. the new course hits a lot of different aspects of electrical, computer, and software engineering, many of which heavily use existing libraries, so they seemed to pick python for this.
in my opinion, they could have easily written libraries in another language, so i suspect there were some politics at MIT that lead to the decision to use python.
Agreed. I only mentioned Scheme specifically because Abelson did in what was quoted.