The dissent may well be right, but the SCOTUS precedent was about a case in NC, where, to the extent I can understand it, a compact minority district was ignored, to create an erose one, and the court was focused on the disadvantaged minority voters in the compact area. Here of course, the old Bonilla district is itself rather artifical, and by no means compact. The old Bonilla district joined some Hispanic voters in San Antonio with others far away in Laredo.
The court was painfully aware that the pending Pennsylvania SCOTUS case could change everything. That is where the action was, and still is.