Great find, and I'm curious who's trying to play a nine year-old single-player average game that's a tie-in to the somewhat forgettable Tron: Legacy movie. Looks like gamers were trying to play this and reported it on the Steam forums and elsewhere, but why this game specifically and why now? Was there a sale?
Really goes to show that games are no different a medium from books or film, and must be preserved and maintained in perpetuity in case that latter generations will want to consume them.
There's what, 20 or 30 years worth of games now, and some of them are still great (e.g. Half Life: Opposing Force). 9 years is nothing. It's even more true for music (luckily that's generally not hobbled by DRM though).