Even supposedly “safe” mushrooms occasionally come up toxic. One or two “experienced” mushroom hunters die every year from consumption of a “safe” mushroom. And, although there are differences, sometimes toxic and safe mushrooms are so closely similar that even experienced hunters get it wrong. Once you stray away from the really well-known species, mushroom hunting has a small but significant amount of uncertainty.
When asked how they tasted, each person said: "Delicious. Just like regular mushrooms."
A long time ago I read a survival guide, which had advice on safe foliage to eat. They said: stay away from mushrooms. They have virtually no nutritional value, and unless you're an expert, it's not worth taking such a risk.
Ref: Clint Eastwood in "The Beguiled".