My instinct is against affirmative action as currently applied, for many practical reasons, most of them covered in these comments. That aside, here is my analysis of the situation.
On the one hand, there is the conservative position that the procedure for deciding the issue is the state-level procedure. On the other hand, there is the at least implicit position of Justice Ginsburg et al., i.e., that it is the obligation of the federal government to ensure that a state doesn't pursue policies which violate the Constitution. (To take an example which puts some flesh on the general statement, without federal intervention the disenfranchising of blacks in the south would have gone on until the likes of Bull Connor deigned to change their minds on the issue.) It is tempting to say that it's a crap shoot and give the benefit of the doubt to the SCOTUS. I disagree with this.
The first question which the court must address is whether the Michigan policy is a violation of the Constitution. It is the answer to this question which then must decide whether the state or federal procedure is to be applied. And it is exactly the SCOTUS and no other institution which must answer the first question. To my great amazement, I can find in neither camp any reference to this simple fact.
The majority decision of course implicitly denies the court's responsibility to answer the central question, but the other side ignores this denial and so, it seems to me, is in no better shape than its opposition.
Or am I missing something?