The issue isn't about race, its about making unnecessary changes to a well established and popular character for shitty reasons.
1) if he's not Clark Kent and the movie establishes this man as a very different person like Red Son for example, that's fine. However, it's a different issue when you basically make him exactly the same only is now "X" race/gender/etc.
1) Fans are always going to look at this as "not the real Superman"
2) DC has actual characters who fill out checkboxes that they could be greenlighting projects for such as Blue Beetle, Cyborg, Martian Manhunter (already established in DCEU now), John Stewart (we could use a new GL movie), Hawkgirl/Hawkman, Static Shock, etc. But instead, we get an asterisk Superman instead of an actual unique character.
On the other hand:
If it's a good superman movie, I don't fucking care.
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One thing about the good guys that I've noticed: they always beg for mercy in the end. Now Playing: Minecraft