At my institution, our students take a series of courses on programming a simple microcontroller (and were doing so long before IoT/Arduino made that fashionable again). We worked with the HC11 until a few years ago when we moved to the 9s12. They even worked for a while in Assembly Language until quite recently (we now use C exclusively). In this case it wasn’t nostalgia or joy or anything subtle: modern computers are too complex to permit a useful mental model of how they operate. These ‘older’ systems (and their modern simple cousins) are a fantastic way to learn how a computer actually works with sufficient insight that it gives you a much deeper feel for how more complex descendants work. As one example, pointers and indirection are always a topic that students learning programming struggle with. Explaining that topic is much, much easier to a roomful of people who’ve worked directly with address registers and offsets.