Things like that have happened before, although probably for other reasons. Some Premium modules (a kind of early DLC) for Neverwinter Nights for example are lost to us, too, because they were only ever offered as DRM-protected downloads and they (Atari?) eventually stopped supporting them (and I'm not talking about the Premium Mods included in the Diamond Edition, because that's only part of the Premium Mods available earlier, maybe even the weaker half, who knows).
Yeah, that's a good PC example. There is also the DLC for original Xbox games which can no longer be downloaded. I know Splinter Cell had some bonus levels and KotOR had some downloadable goodies.
Microsoft letting them host their own servers for multiplayer games and DLC was a stupid move.
Indeed. It just cements this will happen eventually to all console DLC you buy from EA. Since some of my favorite parts of Mass Effect 2 and Dragon Age 2 were in the DLC this is a real shame. Shit even the original Dragon Age... one day Shale will be unobtainable.
At least on PC cracks and backups mean this can never happen usually. The only reason those Neverwinter modules are unplayable is because they had persistent server requirements which basically made them multiplayer only.