compared to other vegetarian protein sources

The person you replied to said this fyi

Grass fed beef is better in some ways than a crop where they apply fertilizers that run off and create algae blooms and nitrate pollutions, and where the strains of the soy in question are GE to take more pesticides.

Pesticides are killing a lot more than we think, a major, if not the major, factor in 90 percent of the insect life on earth disappearing over the last 3 decades.

Remember in the 90's? A summer drive at night would see so many bug splatters on your vehicle you might have to use the windshield washer fluid. Now? Only a few. Something is seriously wrong here.

Insects might stand a chance, but this is just speculation. And only if (as you say) you pick bad/worst case productions like, I don't know, maybe almonds or avocados?

What is the soy being used primarily for? Go look it up. It's not tofu.