I have a MIST, Vampire board, and still play around with UAE from time-to-time... but there's nothing like seeing the "real" hardware for the first time when you were a teenager. Even with all the hardware I've had over the past 30 years, everything else has felt so incremental.
Back then, very few people had these. Now, nearly everyone has something much much more powerful in their pocket/purse or on their wrist.
I do pity younger kids today not having that feeling. The was a mystique around them. Now, it's just part and parcel of everyday life. Everything new now is just an upgraded version of something prior. Back then, it was all so new. I can't think of anything that would have the same feeling for kids today.
Also, it’s a good introduction to understanding full systems, from the electronics—soldering, voltage, current, etc to assembly programming. The system is simple enough for them to ship circuit diagrams in the developer manual—along with all the opcodes and kernel routines.
There’s a resurgence across all fields in artisanal craftsmanship. Carpenters, blacksmiths, printmakers, cobblers.
Retro-Computing is exactly that—artisanal electronics and programming. There’s something meditative and enjoyable about it.
So the older machines are an important conceptual building block. And they're not academic exercises taught in theoretical simulation but never experienced, they're real physical machines that did useful things for people who are still around and can walk you through doing the same things on the very same machines.
The other magical thing about home computers of that era, was that they were ROM-based, with very explicit operations to commit data to nonvolatile storage. You couldn't accidentally delete a system file and render the machine unbootable, and that encouraged experimentation in a way that subsequent PCs harshly punished.
Also, while 8-bit home computers weren't really toys, they were _almost_ toys, in that very few folks were running a business on their C64. (And again, even if they did, all they had to do was lock the business disks in a cabinet at the end of the day.) So the consequences of even a major screwup were limited, again in a way that the next generation of PCs dramatiaclly reversed. I knew kids "grounded for life" (actually a few months) in the 90s because they hosed up the family PC that mom or dad was doing the taxes on or whatever. That simply wasn't a thing in the 80s.
All of learning is making mistakes. One hundred percent. And modern machines don't allow it in the same way. We were privileged to learn in a real-but-nearly-consequence-free environment, which today's kids will simply never experience.