Also people worried about judges making decisions instead of experts is a flawed interpretation, judges only rule on if it violates the law so they don’t need to be experts in the field. Government agencies fall under the executive branch so SCOTUS was telling Congress that they no longer get to pass legislation that is too vague giving the Executive branch room to interpret law which is reserved for the Judicial Branch. Basically they are telling Congress to make better laws and if they don’t judges will interpret them and not government agencies.
They also inserted language to prevent a free for all overturning previous rules under most circumstances.