mushrooms are not fruits in any sense. Fruiting body is applied colloquially however since spores are not fruits this is also incorrect.
However much like with calling a tomato a fruit, it's perfectly clear to call the penis loo lookin' thing a fruiting body and only derranged pedants are bothered by it.
Fruits are a specific part of the plant, the seed-bearing part (pods and ferns are the exceptions, I guess). Veggies are the rest of the plant. Mushrooms are fungi's and all, don't get me wrong, but they're not plants