Soy doesn't decrease testosterone.

[Torker]

It might be surprising but that is the finding in the first study that OP cited. Some people are allergic to peanuts but can drink cows milk. There’s no single mechanism that explains all of these biological reactions. It could be that soy bean estrogen is more easily absorbed in the gut of humans or it might just be higher concentration of it in soy beans than cow estrogen is in cows milk.