I think they’re misunderstanding these recent studies that show the ways mycelium “brokers”nutrient transfer between different plants. There has been some relatively recent evidence that mushrooms will “communicate” with plants with certain nutrient deficiencies in one part of the forest and plants with nutrient surpluses in other parts of the forest. The mushrooms will then transfer nutrients between these plants even if the plants are of different species. It’s actually some really interesting stuff but I think it’s been kinda presented in an elementary way to most people through podcasts or BuzzFeed style news articles.