They seem to have replaced Sr John Gielgud with a slightly overweight Hispanic fellow. I think they may have lost something in the translation, so to speak.
You don't know your Arthurian history very well. :-)
They replaced a black guy you probably never bothered to learn anything about (Ted Ross, who passed away in 2002) with a slightly overweight Hispanic fellow (Luis Guzmán, who was brilliant in Boogie Nights, amongst other things).
They replaced Sir John Gielgud with Dame Helen Mirren, and seem to have remade the story with more focus on Susan.
Look at the trailer again with a particularly jaundiced politically correct eye and you will see Sr John Gielgud was replaced by Helen Mirren, also named Hobson, Arthur's long suffering Nanny.