> I’m not sure that the choice of the language matters a great deal for an intro course to be honest

Huge disagreement from me! The choice might not matter for the already motivated students who were going to learn to code no matter the language, but for folks on the fringe of CS the language matters immensely. There are arguments to be made about frustration, developer experience, grokability, but imo the most important is distance between code and gui. It’s very motivating to build something you can interact with. It’s very demotivating to work on contextually-meaningless algorithm problems.