As has already been pointed out. All of the Silver Age heroes were changed into different people. Except their race was not changed. So you are basically saying that if you like the change then it is not fundamental, but if you dislike it then it is. So again it seems like there just is no room in your comic world for any new characters who are diverse and no changes to the existing ones either. So tough luck to everybody that does not think like you.
For the record changing a character drastically would not be my first choice but when you are dealing with DC they basically got no choice because almost all their heroes are white males. I am glad that started making the effort to even things out. And then we have to be realistic also in the fact that there are only so projects out there and you have to get folks in them somehow.
When I see folks that complain about existing diverse heroes, complain about new diverse heroes and complain about changing existing heroes to make diverse heroes, then I don't see anything but someone not wanting any type of diversity.