Ah, the Quantum DMG of 2024: at once made for new DMs, and also unfit for them...I don't believe they were intended to be run by a new brand new GM, that's what the starter set type stuff is for. My understanding is these are meant to show off the procedure that was presented early in the chapter about how to turn an idea into an adventure. So they serve as examples of what your homemade adventures should sort of look like after you've moved on from running published adventures and want to start using homemade adventures.