justanoldgamer: I don't mind the unbundling but I do have one question/complaint: Why remove the links to the store page? I'm sorry if someone else asked before but I checked all blue's answers and I did not see this addressed.
IAmSinistar: It's likely a database synchronisation issue. Back when the game boxes were generally 1:1 with the game pages, they could use the same key to map one to the other. But now the games have different names than the game pages in a lot of cases, so that association is broken, and they're going to have to code a new way around it.
Just my guess, though.
I believe you are correct, with one exception: "they're going to have to code a new way around it".
Cognition has been unbundled in September 2013 (upon addition to GOG) and has been missing the link ever since. They didn't get around to code it in the last 18 months; I doubt they'll bother now.
Same story for other previously-unbundled games (Dracula 4+5, X-Wing, TIE Fighter).