Why is having standards on lightbulbs a federal issue? Shouldn't it be best handled by the states? Perhaps the EPA or Department of Energy could write a report or make recommendations; but at the end of the day it should reside in the state.
It is not actually the federal government's job to regulate every detail of every transaction that crosses state lines. The specifics of the lightbulbs are only tangentially related to the commercial transaction and even less connected to the fact that it crosses state lines, so I would hardly consider Congress negligent if it declined to make rules for cross-state light bulb shipping.
Nope, but the light bulb plant can choose which states it wants to sell in and manufacture bulbs that meet those requirements. In fact they may just make one that meets the strictest requirements, and people other states may choose to purchase STATE X efficient bulbs.