No code is ever useless, that is the beauty of programming. You can update code and make something better with it. Look at the Unreal engine, they began with a simple engine and look where it is now. Its not like they started over every time.
End of Emperor_Nero's quote
It might be more accurate to say that the code would not translate into anything useful by today's gaming standards. Or to put it another way, overhauling the code to make it into a game that is marketable today would be more work than creating something new and hence "useless".
I am a programmer and deal with a lot of legacy code in my job. The older the code and the more complex, the more likely it is simply more efficient to recode it.
In any event, since Stardock didn't purchase the code, the point is moot. Way to go Atari.