Posted June 09, 2017
The extras started to dwindle because of new games. When GOG was exclusively about old games, every game had their extras put in the package because the publisher just didn't care about charging for it at the game's original release and it wouldn't start with GOG's release. It was gonna be cheap change after all.
HunchBluntley: Maybe the bulking up of the release calendar over the years means that some people who used to seek out and/or prepare extras got shunted to more crucial tasks, like testing.
But once new games got in, publishers wanted to follow the way the industry had "evolved" to in the meantime. Why give the soundtrack for free when I can charge for it? Wallpapers? Artbook? Let's sell it as DLC. Hell, we've had a game I can't remember selling the user manual as DLC. It can't get any worse than that.
Even indie devs do this now as DLC became synonymous with "easy money". Note however how older games released recently still have a higher likelihood of coming with extras than the rest.