It's not directed at legacy admits because they aren't admitted because of "racial consideration". It's a harder case to win, because it's a "structural racism" case instead of a "just plain direct obvious explicit racism, except called 'affirmative action'" case.

If Harvard loses the affirmative action case, someone should absolutely turn right around and start a case against legacy admissions as being racially-biased-in-practice. (However, Harvard has been continually in lawsuits about its admissions for the past, what, decade at least.)

Anyway, what's this "directed at" stuff?

If you take slots away from one racial group because of their race, why wouldn't you expect them to go, "Hey, that's not fair!" regardless of who you give the slots to?

However, if Asians think they'll pick up a lot of slots at Harvard if the case succeeds, they should be aware that Harvard's analysis is that, no, the most gains will be had by whites (https://projects.iq.harvard.edu/files/diverse-education/files/report_of_the_committee_to_study_race-neutral_alternatives_final.pdf). (Note that, oddly, despite stressing academic excellence twenty times or so, they never once reveal how much academic excellence would improve if they abandon their racial diversity goals entirely.) Without seeing the numbers, but knowing the SAT scores, and having respect for David Card's analytical abilities, the only way I can make sense of this is if Harvard is increasing its racial diversity by using "objective" measures that in practice disfavor Asians, and then use explicit racial consideration to pick Blacks and Hispanics over Whites, giving them the overall balance they're after.