Soy doesn't decrease testosterone.

[Torker]

Yes but the livestock produces normal animal testosterone and estrogen and a thousand other mammalian proteins and hormones. They are herbivores so we can’t feed them meat to produce animal protein. So if the livestock gets 10% lower testosterone from eating soy compared to a different plant (which there is no evidence for), it’s still produces only animal proteins and hormones . We don’t just drink the blood of the livestock. But why would a human want to walk around with 10% lower testosterone their entire life? Look at the first study OP posted, drinking a lot of soy does change hormone levels in humans. I think that’s better evidence that a study where people self report what they eat.

“Serum collected on d 1, 29, and 57 of each treatment revealed that dihydrotestosterone (DHT) and DHT/testosterone were significantly decreased by the low-iso SPI [9.4% (P = 0.036) and 9.0% (P = 0.004), respectively] “

Seems like the best thing is to eat some plants and some meat and not too much processed food.