The A1-A20 decks aren’t in any particular order, though. Since they’re writing sentences for them in the order of A1-A20, that creates weird cases where words in the top 100,000 by frequency are getting sentences before words in the top 10,000.
There are common words/yojijukugo not in A1-A20 decks too, though I can’t find examples off the top of my head.