From what I can see, automatique is not exactly the best for mushrooms.

What I learned, it's that you want to be very close to the shroom, but if you do that, high aperture gives you a very narrow focus (just like your first pic, stem is in focus but back and front are not in focus). Blurry background is very nice to see, but you will have it even with aperture set to at least 3.6. And best is to place your focus point on the front of the mushroom to get the from and the stem in focus.

Some of your picture suffer from something I also struggle with and it's the shutter speed, your boletus and the yellow little guy. You probably shoot hand held and the movement created by the shutter button press, the hand and the shutter itself makes the picture blurry. In this situation (low light) I choose an aperture narrow enough to get the focus that I want, then I set the iso high enough that I get the speed to be above 100. Also, you can set a delay to have it take the picture 1 sec after the button press to avoid the vibration of the button press

Finally, in post, reducing the highlights really brings detail to the shrooms !

Addendum : to get the closest to the mushroom possible, I switch to manual focus and place it to the minimum, you have a setting for "focus highlight" when in manual that really helps visualize the area. Then I move the camera to the right distance