That's what my old manager buddy said, he's Asian American.
I'm biased because I've read the book and am a fan of the material, but the book is based on historical events. There was the first Englishman to get to Japan. The was his story. This is historical fiction based on real life events. Would you want to see a story about a white guy who gets to Japan in the 1600s and gets murdered immediately? If you're not familiar with the book, they are very layered and 1200 pages and shows the events from the Japanese side as much as the Englishman's.
What do you consider a white savior? He plays a huge part in the ongoing war and politics, but he doesn't "savior" anything...Japan is a military feudal society when he arrives, and it was a military feudal society after he died. He has knowledge of the world the Japanese wouldn't have had. The Europeans were vastly technologically ahead of the Japanese, this is just reality. I can't say how it ends without spoiling it, but it might not be how you expect. You might even claim that the real main character is the aspirational Shogun, and his story is told through the eyes of the white savior.
Nice seeing a real Portuguese actor playing a Portuguese priest...Joaquim de Almeida love that guy in everything I've seen him in.