It may not be possible for foreign filmmakers to increase the demand for their products in a way that would rival the demand for American-made films, but they certainly ought to be able to stimulate a much bigger demand than is currently the case. Some very excellent films made in countries such as France, Germany, Japan, China, Iran, and the United Kingdom show box-office results in Weekly Variety of only a paltry few million dollars while run-of-the-mill Hollywood films are earning hundreds of millions.
The obvious way to create demand for films is through advertising. Many foreign films come and go without the public even being aware of their existence. Many foreign films are only shown in New York and Los Angeles--and some are not even shown in L.A. All foreign filmmakers might get together and pool their advertising budgets to publicize films in the major American cities. If they spent more money on advertising, they would automatically get more reviews in the newspapers and magazines.
Naturally the foreign filmmakers ought to pay attention to which foreign films do well in the U.S. and try to produce more such films. They might experiment with using some American actors and actresses in their productions--not as stars but as supporting characters. They ought to be able to offer exhibitors more lucrative terms, so that it would be more profitable to show some foreign films. No doubt there are many foreign filmmakers who could double their U.S. gross revenues if they made the effort. It does not seem that any have made a strong effort.