There's a lot of pressure to teach languages that are widely used in industry, which is why so many students come out of university knowing mostly Java. There's also a lot of bias against "old" languages, and for newer, trendy languages.
Teaching SICP in Python is just a further development of that trend.
Software engineering is a very trend-following, path of least resistance, bandwagon-jumping profession. If "everyone" is using language X, that's where most engineers (and managers) want to be. Universities are just satisfying that need.
It's a wonder that Scheme lasted in universities as long as it did. It'll be interesting to see how long Python lasts.
There's always Clojure. Best of both worlds, i.e. Scheme-ish with Java host. We had a SICP Clojure group here in London last year and I think someone has written an adaptation of SICP in Clojure. If it was any other text I'd have nothing to say but SICP without the Scheme/Lisp doesn't make sense. If universities choosing Python or Java as their teaching language they should also switch to texts based on OOP.
Why doesn't it make sense without any LISP? I read only the first chapters and found the concept of composition immediately applicable in C and as a C programmer I would write the same way in python, probably.
Remember, all of those "old" languages, when they became notable or influential, were younger than Python is now.
Scheme, when SICP was written, was only 15 years old. It was young and trendy at the time.
C was less than 20 years old when I learned is as part of a required course for my CS degree. I've no doubt that part of the reason was that it was widely used in industry.
C++ was the trendy thing by the time I left school. It was less than 10 years old.
Perl was 10-15 years old when it was used as the "Swiss Army chainsaw" for a lot of the first era of web development.
While this appears to solidify your observation that software engineering is very trend-following, I listed them to point out that Python seems to be the oldest language when it made the jump. It's surely older than most of the students and even TAs for the course.
Python has been a common teaching language for at least a decade now, it's just that this particular course has now switched to it as well. Still took 15 years for it to get that momentum, though.
You won't see a CS course taught in Go or Rust anytime soon.
Teaching SICP in Python is just a further development of that trend.
Software engineering is a very trend-following, path of least resistance, bandwagon-jumping profession. If "everyone" is using language X, that's where most engineers (and managers) want to be. Universities are just satisfying that need.
It's a wonder that Scheme lasted in universities as long as it did. It'll be interesting to see how long Python lasts.