Instead the financial rewards are on instant gratification “hits”. Never mind that the public will watch a King Kong, Gone With The Wind, Greatest Story Ever Told, or Laurence of Arabia for decades bringing in much money to the studio (and those involved).
Was it the “biggest non-holiday opening weekend ever”? If not, pull the ads after 3 weeks.
In all fairness, for a few brilliant films that are remembered by the public today, there are thousands of brilliant films that only bring in a few dollars of royalties each year. And even the ones you mentioned are not huge money makers anymore.
Much of the problem is in the delivery of the product to the market. Movie theaters need a different social setting than the one they’ve had since the beginning. That is, the theater pays the box office to the film distributor, and makes its money from concession sales.
They need some other means to draw in the crowds, who can then “also” watch a movie.