Here is my take. If a Bond girl can be black, which they have had, then there can be a black James Bond. If he is part of the agency, and from the UK, then it works out. It can't be someone like Diddy.
Plus Elba has a thing for cars and the like...which suits Bond perfectly, and has that smug look that Sean Connery was known for.
Sure they can do what they want. Black bond. Female bond. Transgender bond.. Maybe if Speilberg bought it Bond could be a robot or an alien.
But it's quite silly this PC trend.
Much of the Bond appeal to me is the symbolism of old values like sexism and conservatism (and patriotism).
The world of Bond should be like a travel in time.
There has been a continous stream of Bond movies since the sixties and the recognized formula/look of Bond has always been pretty intact and - I would hope - that was has made the concept successful for decades.
Only recently, when Q died and M became a woman the classic feel began to dissolve.
A white shaft is a good example of how silly it all is.
I would never want a white guy playing Blade or a male Tomb Raider for example.