Germany and France each produce just as much or even more content than the UK.

Yet, none of this content ever leaves the country. British content can directly be sold on the US market, which means they can get much more money from those licensing deals to finance more productions.

The only situation where German or French productions show up internationally are nature documentaries (many of the documentaries the BBC or PBS show are produced by Germans, or as cooperation).

The English-speaking market is so large that English productions always have an advantage, and US productions even more. A US production reaches 300 million people in its home market, and a billion globally. A German production reaches 80 million in the home market, and 130 million globally.

And that's without the venefits hollywood has from having all the actors, staff and technology in one place.

This battle has been decided long ago.