This is the current mnemonic for this Level 22 vocab:
Remember blood pressure (血圧)? Well, now the blood pressure is tall… so you have “tall blood pressure.” Well that’s dumb. Let’s call it high blood pressure instead.
The idea, though, that 高 represents high is nothing new, introduced way back with the kanji in Level 7 and reinforced in Level 9 with 高さ.
Thanks for pointing this out (and sorry for the delay - just got back online after being away)! We’ll put this on our content team review list. If anything gets updated, it’ll be posted on our Content Updates category.