The western was already sick by the 70s but Heaven's gate was like a bullet to the brain for the genre. Even in the 70s, less films were being made but the ones being made were still at least profiting. That all changed with Heavens gate, one of the biggest money losers of the 80s. From that point on, westerns basically ceased being a genre that you can actually make money on, with the exception of Dances with Wolves, Unforgiven, the true grit remake, and a few others (young guns, pale rider), the number of western films since Heavens Gate which were actually considered hits for the studio can be be counted on one hand. More often than not, westerns lose money, The Alamo, Jonah Hex etc... and the upcoming Lone Ranger movie is going to lose money for sure. Even an excellent western like 3:10 to Yuma barely made back its production and print and advertising costs, and thats only because it had strong home video sales. Nowadays Hollywood relies on films that are not westerns but have western elements to turn in a profit. An example of this would be No Country for Old Men, as well as the Book of Eli.