what qualifies as a key characteristic for a purely fictional character, I wonder? I guess for a fictional Russian spy/assassin like Natasha Romanova/Black Widow in the MCU, casting a white actress makes sense considering Russia's ethnic make up and so no Halle Berry... how about a secret agent in Europe that may need to go undercover or blend in and yet be black or Middle East or Polynesian in appearance? hard to go grey then... then again, part of the Bond persona is standing out to the point he tells people his REAL surname TWICE - "Bond... James Bond!"
let me ask you a different question... Germany now is a pretty multicultural country, too, with ethnic Germans making up about 75% of the 80+ million population... there are a lot of Turks, a lot of Africans etc. in Deutschland... but what are the chances any reboot of Die Hard would involve casting a coloured Hans Gruber? none... something to ponder why
now, I am not against updating/changing characters and stories and franchises if those decisions are made creatively... for example, Bond is introduced as a Beretta carrying, WWII veteran in "Dr No"... Daenerys in the books is like 14 years old when they start but the "Game of Thrones" showrunners rightfully cast a 24 year old Emilia Clarke considering some of her scenes in Season 1... but if it is diversity for diversity sakes, then no
one last thing... Ian Fleming himself said Bond resembled singer, Hoagy Carmichael