Rise of the Triad, Fortress of Dr Radikai, Corridor 7, Blake Stone, Eradicator, Aliens, Powerslave, Witchhaven, and on and on. All of these games did poorly, not because there were too many 3D shooters out, but because, in my opinion, they were poor games. But games such as Duke Nukem, Dark Forces, and Jedi Knight did very well because they are well-made games. Same themes, very different results. The major lesson is that ideas are a dime a dozen.
Execution is the key'.
I'm not sure that the games industry is really about raising issues. Gavin Rummery raises a slightly more militant issue. Most developers are in it for the love of games, but the gradual takeover of the industry by the corporate types has led to games as products.