"l Pacino was unfairly mocked in the UK for pronouncing Duke dook in Richard III. I am surprised to learn that American and Canadian Shakespearean actors go for Brit accents “
Some people are ridiculously, and somewhat ignorantly, precious about this kind of thing. There were people who complained about American accents in Prince of Thieves, or even First Knight, but there is no sense in which the modern British accents are more similar to those in King John’s England (or mythical King Arthur’s England) than modern American accents are.
Then again, people complained about Harvey Keitel’s accent in Last Temptation of Christ. Some people just like to complain.