The divide seems to have formed over political expectations.
Summed up, white churches are not feeling the guilt over slavery and Jim Crow, and are not talking asking forgiveness for stuff they did not do.
White churches are not sufficiently beating the Social Justice drum.
White churches are not buying into the Bad Policeman narrative. Dude ambushes five Dallas policemen and they want to talk about bad policemen next time they get together?
White churches are not wanting bigger government.
White churches do not vote for leftist, pro-abortion, big government candidates.
So black people are leaving. It’s not about doctrine.
Its about politics, not religion.
If you’re a religious person, politics plays a secondary role in life.
For liberals, politics is religion.