I've thought this myself. We sure do consume a lot of yeast-based foods. Entire industries created to cultivate the stuff.

I thought it would be an interesting story about how the bakers and beer makers are the actual illuminati, consciously working on behalf of the yeast which is our actual over-lords.

Ha. Different bug (sentient yogurt cultures) but sort of explored quite amusingly by Love, Death & Robots Season 1 - https://lovedeathrobots.fandom.com/wiki/When_the_Yogurt_Took...