Many people are allergic to gluten which is in soya
"Soy is naturally gluten-free"
source:
https://nationalceliac.org/celiac-d...ducts-ok-to-eat-when-you-have-celiac-disease/
"Soy itself is gluten-free."
source:
https://www.beyondceliac.org/gluten-free-diet/is-it-gluten-free/soy/
Both of those websites are intended for people who cannot eat gluten, so I assume they know what they are talking about. They both point out that many soy-containing foods ALSO have gluten, but the gluten does not come from the soy.