The whole "it's okay to be white" thing is a dogwhistle to begin with. It might seem benign, if weirdly unprompted without context. The issue is that among some groups this is often followed up with accusing black movements and immigrants of wanting to get rid of white people, rather than just seeking equality, which is done to fuel racism. This is why a lot of black people might be suspicious of that statement. Nevermind that not agreeing with it might simply mean unsure rather than against.
This whole thing is a roundabout rhetorical play to bait people who are more afraid of being accused of being racist, you know, because racism is bad, than understand that racism has a whole history, that black people have good reasons to be wary of people who are a little too proud of being white. But detached white people might be fooled by a superficial read of "why is it okay to be you but not okay to be me, maybe you are the racist".
If anything he proved that he is exactly the kind of white guy that black people might be worried about. He doesn't care about them unless he's on the "winning team" and gets a reward for it.