It's only politics on dumb places on the internet that people want to argue it. In reality it's actually business. We live in a diverse society, and the industry itself is diverse. It's long past the days of white Hollywood for white America, the film industry is global now.
A good example that someone else brought up, anyone getting into acting these days whether film or theatre is going to come across doing some Shakespeare. Should roles in big Shakespeare productions be reserved exclusively for white people because that's the historical era? It's one thing if it's a movie like The King or a show like Vikings, but fantasy like theatre doesn't really need to stick with it. I mean think of video games for a minute, LotR has inspired tons of 'European' themed fantasy games. They usually come with a character creation screen where you can change the skin tone of your character, and I've never seen anyone complain there.