If “every moving thing that liveth shall be meat for you” (Gen 9:3), does that not mean that there was no unclean meat?

So it appears, and this is despite a statement not long before (Gen 7:2) that some animals were “clean” (טָהוֹר, tahor) and others not. Some commentators attribute this to two different authors of the text (the P, or priestly, text would talk about clean versus unclean animals, while the Gen 9 verses would by from something like the J, or Yahwist, source. This, of course, undermines the credibility of the text. Is there another sensible way to reconcile the text? Perhaps this way: Moses would describe tame livestock raised by Noah as “clean,” even though Noah might not; he might attribute those words to God, and who knows, perhaps God employed them with Noah. But times were simpler, and God was permitting all food sources to them, so that they had the best chance to succeed in life.