Okay so knowing things = invested, okay. This is all information that is readily available in the game, you get it as part of the main questlines. The whole cancer treatment is due to Blizzard publicly having likened the Old Gods to a cancer in Azeroth, and that was then abstracted to information about cancer treatment that I happen to know, which is also easily available.
You hear people who are into the whole Old God thing hearing the term and then subconsciously connecting them with the C'thulhu mythos, which ever since we heard about the Void Lords was invalid. The Old Gods in WoW = have bosses. The Old Gods in the C'thulhu mythos = are the bosses.