One thing that I think that is important to understand is that these machines, and this code, is still out there, working. People are still playing these games (MAME) and the emulation scene that has arisen due to the fanboix fervour has really pushed a lot of the gems into the 21st century with new life and vigor. The "automatic game player"-coded-in-z80, i.e. hardware playing hardware, is a real hoot!

And last but not least, consider this: people are still writing amazing software for the older architectures, using modern principles, and learning astonishing new things about the "antique hardware", to boot! In my particular nook I have witnessed the Oric-1/Atmos machines (http://oric.org), typically considered a fairly "grotty" 8bit machine of the 80's, never enough decent software, died early .. yet now come to new life with the discovery of never-considered color-modes and graphics capabilities by some of the modern scenes very elite hackers, turning their eyes to the "old" machines and producing new hits!

I think a lesson in all of this is that the old machines still contain a lot of power. The robotron code could probably be refactored into something else, easily enough, if there was some intention behind doing it. There are a lot of 6809's out there, still, presumably in landfill its true, but nevertheless one could do worse than to re-discover old machines in the modern era, were one to want to sharpen ones skills ..