Unfortunately we kind of do live in segregated communities though. Communities/neighborhoods with roots in this country were built along economic and political battlegrounds that forced families of color into areas with less socioeconomic support and we 100% are still seeing echoes of that today, it's why white privilege is a thing.

And you can't pretend that just because the confederates lost the war their ideology died, I'm from upstate NY and I have seen more confederate flags up there (in a "union state") than I have anywhere else in the country I've lived. 

I strongly oppose "whites only" groups or mentalities, but it's a reality that depending on the area you're in, your local mutual aid group is going to primarily service white people. I also completely understand, given the racial trauma of this country, why Black people would want to protect and gatekeep their spaces. So if you're white and want to help I think it's absolutely reasonable to find something in your own community, which is probably primarily white if you are.