Zero speculation regarding the diets of chimpanzees, orangutans and gorillas (well studied and documented) [1].

[2] B12 sources up until it was possible to synthesize in the 60s were exclusively from animal products. Also, if you're even vaguely predisposed to anemia, you will likely struggle getting enough hema-available iron from plant sources without supplementation.

Glad you are able to live off of entirely soybeans, legumes, grains, nuts and seeds. For a lot of people, this isn't sustainable. Would love to see your bloods, discuss athletic performance and energy.

[1] https://www.scientificamerican.com/article/diet-and-primate-....

[2] https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessio....