For the umpteenth time, the race of the elected official does not determine whether a district has "regressed"or not. We've been through this every previous time this has come up. Note that according to this poll, Clarke gets less than half the votes of the African Americans surveyed.
1) For the umpteenth time, the claim I read in this forum is that regressing a Black VRA district to the low forties would not result in Black incumbents losing. Can we acknowledge that that claim simply isn't based on fact? The advocates of that claim hand-waved away the democratic primary in favor of solely analyzing the general. In the real world, minority Democrats are being beaten by White Democrats when their districts are being regressed to the low fifties.
2) The claim that I have read here is that when a minority carries his minority's vote, but a White beats him based on White support, something untowards has happened. [I've even read the claim being made that Blacks voting against the "preferred" Hispanic is equally untowards.] It seems that Clarke will be the "preferred" candidate of the Black electorate, while Peters will be the "preferred" candidate of the White electorate. That is the test I've read being asserted for what is "regression."
MI is not a section 5 covered state and Wayne is not a covered county, so regression does not apply here. Section 2 is the only applicable section and it requires that if there is a compact area with 50%+ BVAP large enough to make a district and there is evidence of cohesive voting patterns by both whites and blacks, then there must be a district drawn that could elect the candidate of choice of the blacks. That candidate need not be black, but the question as to whether the district must have 50%+ BVAP has not been settled by the courts. Individual states have been successful in defending maps with minority districts below 50% BVAP, but it isn't established on a national basis.