I'm no expert, but I think you're wrong here. Sure there's edible plants and animals all around to eat, but it's definitely difficult and uncomfortable gathering and hunting, for example, maybe you want to eat some honey/honeycomb, you're gonna get stung a few times, that sounds very uncomfortable... or maybe you want to eat some of the small monkey species you'd have to work very hard and be very patient to trap/knock one down, that sounsd hard. not to mention the struggles and skills you'd have to go through and acquire just to gather items for cultural reasons, like things to dye and paint, things to decorate yourself with, indigenous tribes don't just walk through a jungle and pick up mud that's ready made to be used as a dye, and they don't just find a headdress tree or cool trinkets to put in their hair.