I dont think its rascist to want a character that's been typically white to stay white.
The same as if a character that was typically black, there would be complaints if that characters race was changed.
There was similar outcry when when they made the character a female. I personally agree the sex shouldnt change of a character. That's just my opinion.
Same argument for the 007 character, it should alway be a male no matter what race he is. Again personal opinion but I think Idris Elba would be great in the role
Some people just dont like change . Which is a bit odd when it's about a character that periodically changes appearance