This Federal vs States has already been determined. When states and cities decided that they would give sanctuary to illegal aliens the Feds should have stopped it as a breach of Federal law. They chose not to. That set a precedent for ignoring Federal law. It may come back to haunt them. What Federal laws do we obey and which can we ignore?
I guess my point is ... what Biden is doing is not Federal law. It is less than that as it is only an executive order.