The question in the Harvard case is about Title VI, not the 14th Amendment. Iirc Justice Gorsuch asked Solicitor General Prelogar about applying Bostock's interpretation of Title VII's prohibition of sex discrimination to Title VI's prohibition of racial discrimination. I wouldn't be surprised if the SFFA ruling(s) is/are at least partially rooted in Title VI, especially considering the contested history of the 14th Amendment.

I wonder if the Bostock test could be applied to race-conscious admissions policies as well. But idk if Gorsuch would get the votes for that, as it'd cement Bostock when there is a flurry of post-Bostock litigation in the lower courts.