I think you're missing the point... the software itself is copyrighted, that means that the owner of the copyright sets the terms and conditions for _anyone_ to make a copy, With statutory damages up in the stratosphere, no one here is likely to bootleg a copy of the media or host iso images of the CDs. Its' really that simple -- autodesk owns the bat, ball, and playing field and they make no money by making old versions available. And money is the only reason the CEO has to do anything...
what is legal is to sell/transfer the original physical media, and if I had a 2004LT CD i'd be happy to sell it to you for a reasonable price -- say half what an annual rental fee would be. Sadly, I don't