Judges are expected to write opinions not only for the sake of precedent, but b/c written opinions act as judicial guardrails. They help keep judges from making arbitrary or insufficiently considered opinions because they have to provide some coherent explanation for their conclusion.
Amy Coney Barrett just told Congress that it would be inappropriate to explain the reasoning behind the Court’s unreasoned shadow docket orders. As if unreasoned judicial orders are a thing. They are not. The reasoning is the whole point.