I'm not sure I buy the argument. Nothing lasts forever in Hollywood. And the dramatic and sensationalist innovators weren't really opposing camps: someone like Coppola or Scorsese could bridge the gap between artistic and popular film. Maybe, in his own way, Spielberg could as well. But the argument can't simply be dismissed or ignored.
Spielberg killed off the disaster film. The fact is that the industry was going bankrupt in the 1970s and as the studios were being sold to multinational corporations and run by people who had no background in film, it became a bottom line business. It would have happened with or without Spielberg who made better films than most of his contemporaries. Close Encounters certainly wasn’t pandering to any particular market. It was pretty daring. Even E.T. was financial risk...in 1981 films about children had been regarded as box office poison for almost 20 years.