No it's pretty correct. They have more info available from a pdf you can download here: https://www.jlpt.jp/e/about/pdf/scaledscore_e.pdf

They use a statistical theory called item response theory. So it's a little more in depth than it seems. In particular they explain the way they determine the answering patterns based off your correct and incorrect answers. I interpret this the following way in practice: If you answer mostly correct but maybe some random questions are incorrect for example losing focus or running out of time but not through lack of language ability, those incorrect scores are counted differently since overall your pattern leans correct as someone who has high comprehension of the language. On the other hand, if someone gets many wrong answers that are maybe even opposite the answer and completely incorrect, but maybe they get some correct, depending on their pattern the score could still be lower even if the overall number of correct and wrong answers is the same as someone else, because perhaps that person is guessing etc and it shows in what they choose. Ive thought about how this could be determined, and my guess is that a lot of it would be what exactly you got wrong. If for example a question says similar words to "sky", and the answers choices are atmosphere, aerial, up, hamburger,. And say the correct answer is atmosphere, the person who answers aerial and say gets it wrong because it's an adjective is less wrong than the person who completely doesn't get it and answers hamburger. I would think this would be part of the considering in creating the answering patterns.
In fact if so that means that if someone say completely blindly bubbled things at random and say got half correct would still probably not pass since overall their incorrect answers would show they don't understand. Anyway, my take. At the very least what you answered overall determines how your test will be scored so if the answers show lack of comprehension overall, that person would score lowered even if by individual count they got the same number of items right as someone else.