It is no big secret that all of the content is now open source.
You could make it into your own Anki or other deck. It would take work and effort, but so does WK. I made paper flashcards for my own personal use from the WK data. Nothing prevents you from doing that either.
Or, for the cost of a one year subscription, you could get to level 60. Plenty of people do. It is less than the cost of a single textbook.
But I am aware that is still more than many can afford. I am not trying to be totally cavalier here. Really though, you can look at the level 4 radicals, draw them out on paper and memorize them, then do that for the kanji, then do that for the vocab, then keep going until you get to 60. The resources are there for you, with no legal restrictions for your own use.
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