Can I add old computer programming courses to the new Classroom?

I don't think they're abandoning either course; they just added a new Unit 7 to the Python course about a year ago.

Is this a new difficulty that started with Khan Academy Reimagined?
I've started a post to try to get teacher feedback on Khan Academy Reimagined; if you have been using Khan Academy in your classroom both before and after the change, would you be willing to post your feedback?

(I'm just another user, and I don't know if KA will use the feedback, but I think it's worth trying.
I don't remember seeing a single comment in the Support Community that says a teacher likes anything about the change. I've seen several saying they dislike aspects of it, and several saying they really want the old interface back.
I don't even know if KA had any classroom teachers test KA Reimagined; maybe KA staff just guessed what teachers wanted based on Support Community posts.

If far more classroom teachers dislike the changes than like them, KA should roll them back.)

~ Janice, KA user

They still offer the Python and the old Javascript courses, but you can't pull them into the new Classroom.