I found this old interview of James Earl Jones by Dick Cavett. Anthony Quinn (a Mexican of Irish descent) had planned to make a film about the Haitian Emperor Henry Christophe.
It’s fairly clear that Jones doesn’t think Quinn should play Henry Christophe but he makes his point in a very nuanced, sophisticated way that’s far more convincing than the absolutist arguments you here on social media today.
I also think Jones would have made a great Beethoven(when he was in his 40s, although he’s probably a bit too old now at 88). For what it’s worth, Quinn was quite convincing as a Libyan in the film Lion of the Desert.