Athanasius said:
Actors are supposed to play people they aren't.
This bothers me zero. And those of you it does bother, you're position is no better than people complaining that the voice of Simba (an imaginary talking lion) should be voiced by a black person, because talking lions are only… black people, I guess.
Are you also offended they are letting humans play elves?
I do, however, hope they don't ruin it with a glorification of sin. Tolkien would surely disapprove.
If and only if the source material doesn't do an adequate job of world building. JRR Tolkien did quite the opposite. He was a master world builder down to the descriptions of the people inhabiting that world. Remember he created something that would be a kin to England's mythology. Where do people of African descent play apart of England's ancient lore?
The problem with Amazon's adaptation is it's a "prequel" to his stories that was set in the 3rd age. By them going before it to the 2nd age they have opened a very uncomfortable can of worms. In order to get to the people of the 3rd age, Amazon will need to justify or explain some kind of mass genocide event to 'undo' the people to get us to the 3rd age.
I'm fine with characters being what ever race they want as long as it doesn't contradict the source material. Our position is no where near that of those of the Lion King. If you can't see the difference between the two well that is on you and you can stay ignorant.