Brian Harvey explained the decision to switch here:
"But, as I keep saying, the choice of programming language isn't the main point. I get upset when students, even the students who like 61A, refer to it as "the Scheme course." It's not a course about Scheme! It's a course about programming paradigms. MIT, where SICP was written, no longer includes that course in its lower division core sequence, not because they wanted to change programming languages, but because they changed the entire sequence from courses organized around big groups of ideas to courses organized around application areas: first "let's build and program a robot" and then "let's build and program a cell phone." That's a brave and thoroughgoing attempt to, among other things, attract non-nerds to computer science. To say, as some people do here, "MIT switched from Scheme to Python" completely misses the point of what MIT did; nobody is proposing any change half as profound at Berkeley." [1]
That's Berkeley. Abelson and Sussman once got MIT to trademark "Nerd Pride".[1] MIT still keeps the trademark active. Here's a Nerd Pride button.[2]
[1] https://books.google.com/books?id=LJq0JhoElk8C&lpg=PA78&ots=... [2] http://www.computerhistory.org/collections/catalog/E1312
[2] http://www.computerhistory.org/collections/catalog/E1312
2. I think you are focusing too much on the use of the word "nerd" here. Harvey chose the use of that word, not MIT.
The common phrase was that you should be made to take 61A as your first class and as your last. You really dont fully comprehend it until you get wider exposure, but you need that initial exposure so your brain can begin to knit things together as you see them.
Meta-Circular Evaluator RIP. You will be missed.
Having done the intro course in Scheme, I'd say it helped me understand functional programming far more than I ever could have with Python, and it opened me up to different ways of thinking.
Even though I never again used any Lisp variant, I'm still really glad I learned it and feel that what I learned using Lisp has informed my future decisions.