The pi is a cheap development board. it can do and be used for a million things. its a developers dream. and though not as powerful as a modern pc its cool that you can use it for emulation or creating a miniature arcade machine cabinet that works.
honestly does anyone care about "accurate emulation or about hardware preservation". doubt it... people care about game preservation. being able to play all their retro games that they grew up with. the rest is working with what you got.