Regarding that link to a court ruling that allows copyright laws to be ignored for the purposes of cracking games that are no longer distributed or updated by their publishers...
While it is true that the ruling does not make the distribution of abandonware allowable, (as the article itself points out,) there are very few, and extremely rare, cases where abandonware distribution is brought to court.
In those few rare cases, it is also still a civil offense under US copyright law; not a criminal one, and from what I can tell, the vast majority of those cases were settled with the "offender" simply stopping distribution of that specific IP, and that's it.
Nothing more than an "Okay, I'll stop."
This is probably because, while still held under copyright, those IPs were no longer being worked on by anybody, meaning no loss of sales due to the distribution can be proven.
(It's not being sold, so the IP holder isn't going to be making a profit from it anyways.)
Again, this doesn't mean that distribution of abandonware is strictly legal; but it does mean that it is not criminal.
(Under US copyright law. Other countries may still have criminal ramifications for this type of distribution without financial gain or loss.)
In terms of older games specifically; while one of the major draws of GOG is in fact the ability to download and play games I used to play, with compatibility patches that make it easy to do on newer systems.
(Even for myself, a veteran in getting old games to work on new systems, and new games to work on underpowered systems at a fair frame rate.)
That said, there are many titles that I would love to play again that I simply can not find.
(Actually, there are a few titles that aren't available anywhere I can find that I happen to still have on floppy disks, and old 20GB HDDs.)
Personally, my favourite place to find these old games for the last 8 years or so has been Abandonia, mainly because they will remove the ability to download games at the request of their IP holders, making it a little more legitimate in terms of copyright law.
Effectively, they take the least gray of the gray areas regarding US copyright this way; ensuring that old games that are no longer sold and supported are still available, while providing listings for games that are actually still be sold.
(Amazingly, there are actually a few games from the late 80s to early 90s designed for MS-DOS that are still being sold.)
Regarding newer games, there is a huge list of things that could technically classify things as abandonware, or not.
For example, the Red Faction series has been retired by the current IP holder, and no plans to make new games, or update old ones, has been made for the foreseeable future.
Does that make the franchise abandonware?
Only games in the franchise unavailable for sale anywhere?
It's weird, copyright law.