I dabble a bit with ROOS and RISC OS Direct on my Pi 4. Being from the US (and a solid middle-class early 1980's childhood), it is quite unlike anything I'd used then or now. The integrated BASIC interpreter takes me right back to my childhood and my old 6502-based Atari (I believe Macs at the time cost about as much as my parents would spend on a car so they weren't even a dream), and demonstrated that my memories of fun weren't as rose-tinted as I thought. I enjoyed the experience enough to wish I had a "proper" desktop RISC system with storage beyond just USB or the flash cards on the Pi.
What a great platform.