Although the plaintiffs claim to be pursuing a systemic claim addressing widespread shortcomings, they aren't challenging a policy or practice of general applicability, but rather pointing out several instances in which the system didn't work correctly; administrative exhaustion is therefore required in order to develop the administrative record and give the state a chance to remedy the situation.
https://cdn.ca9.uscourts.gov/datastore/opinions/2021/08/18/20-15386.pdf