Been studying plant-fungal interactions for about 10 years, including a master's degree I dropped out of and never actually finished* so I'm full of fungus facts i don't really get to use ever.
*Actually did all the course work and lab work but didn't finish my thesis in time
Yeah I've foraged. Mostly in the (comparatively) dry-ass areas around Davis, CA, and didn't find more than one or two edible mushrooms per trip, but I got a chance to go out with a friend near Portland and dammmmn they got a lot of mushrooms there.
Oh one cool thing you can try when you forage, if you find a tasty mushroom you can pull up a little of the dirt around its base and try to culture it from the mycelium attached there. Cardboard is a decent, easy to sterilize starter stubstrate, then if you have a variety of wood (or manure or whatever) to play with, you can see if you can find one it likes. Though there's a good chance it'll be mycorrhizal and you won't have a ton of luck, it's still fun to try.
I really wanted to grow lion's mane but it died on me. And if I had the space/time right now I'd probably do king oyster, I think it's a lot tastier than standard oyster but hopefully it'd be easy to grow because it's an oyster.
ahh yeah, it's so hit or miss, and it really depends on the local climate and the particular forest - don't quote me on this, but i think i read that nitrogen content in the soil in the region correlates with the degree of bacterial vs fungal decay you get. i went out a few times in the bush near where i grew up in southern ontario and there was hardly anything, but then at my old summer camp a bit further northeast it was like a fairy kingdom in september. we found a few semi-edible types like pepper milkcaps, as well as a small cluster of chanterelles and a rare, bizarre kind whose name escapes me that was incredibly sweet
i'll have to try that trick next foraging season!