Yes. The idea is that if you see a new word that uses kanji you already know, you should have a good chance of correctly guessing its reading.
Kanji that are put together (without ひらがな) almost always use the on’yomi readings. So yeah, a vast majority of the pink kanji reviews are asking you for the on’yomi. You can use this script to keep straight which readings are which: [Userscript] WaniKani Katakana Madness
It’ll make your kanji (pink) reviews display on’yomi readings in カタカナ 