What is the goal of a project like this?

I'm absolutely not meaning that as a pejorative. I am just curious if there's an actual goal here. Is the goal to make a faithful reproduction, historical reference, a hacking challenge, or? Is it just curiosity?

I see lots of links in the thread, many for different games. Curiosity is as valid a reason as any other, but is there some sort of end result trying to be had? The various links don't actually seem to enumerate this very well, unless I missed it.