The 8-bit home computers of yore that we all know and love, without exception as far as we are aware, had an off the shelf microprocessor at heart. In 1983 you were either in the Z80 camp or the 65…
From look at the board, basically it looks like they did the "hardware" emu approach.
But people I know that enjoy retro stuff they either want the look(original or replica case/keyboard, but internal is more modern that runs software emu) or they want the antique(functional original). It's pretty rare to see these kinda of hardware emu where they bundle chips as close to old ones while trying to replicate how the old hardware work and then drive with another modern board for the input/output.