My brother is a public high school teacher, so I'm somewhat familiar. They're to schools, where the objective is to have something that's cheap, easy to administer, and locked down. They also tie into Google Classroom/GSuite and have limited local storage. Many Chromebooks aren't given to a specific student, but rolled out in carts and handed out during a "computer lab" time.

While a Mac would work, a cart full of Macs is radically more expensive than a cart full of Chromebooks. A family friend is a music teacher that uses Logic, so maybe that's a use case, or iOS development.

Well, I think it all depends on why someone is buying a Chromebook.

Is it because they want a cheap clamshell with a keyboard? (Tablets adjust poorly to this use case.)

Is it because they want a cheap general-purpose computer?

I've seen enough non-institutional users of Chromebooks to see that there is a market for them. (I had one of the original demo units and really liked it.) I can see why Apple would want to get a piece of that market.