I don’t know any Japanese but for Chinese, metrics like this are misleading, because the long tail of unknown characters are still enough to prevent you reading

I don’t know any Japanese but for Chinese, metrics like this are misleading, because the long tail of unknown characters are still enough to prevent you reading. If you know 80% of chinese characters by frequency you can’t read 80% of the newspaper, it’s probably closer to 10%. In other words, comprehension does not scale linearly with number of characters recognized, it’s more like a step function.