At the very least, a sample map in the dungeon section explaining how to use it and stock it. You know, like is in the 2014 DMG and every DMG before it. The sample adventures are laughable in that regard: they literally tell the (assumed to be completely inexperienced) DM to modify the map to make it better fit the plot. Not show them how, not give them maps, just offhandedly say it.
I don't know why this is a controversial opinion other that people getting their backs up anytime anyone suggests WotC did not do it perfectly. The 2024 PHB and DMG both have serious organizational issues, and the DMG while doing a very good job of explaining play and the DM's job fails to explain the most basic unit of D&D adventure design: the dungeon.