I love xkcd. Most of them resonate with me. However, for some reason #1053 (number three on this list) does not feel right. Maybe it’s oversimplified. I don’t think linear interpolation works in this case. Most things are learned in bursts at certain ages. Then again: maybe I’m wrong and need to learn this! https://xkcd.com/1053/
https://www.explainxkcd.com/wiki/index.php/1053
I think it is funny and amazing, that there is a whole dedicated wiki about xkcd.
(I do not know, whether your concern is adressed there in detail, but probably it is indeed just oversimplification)