Soy fixes nitrogen and doesn’t affect the rest of the nutrients. Without soy in the crop rotation you have to simply buy more nitrogen fertilizer for the subsequent crop, which will make it more expensive to grow. Soy is good but it’s not a looming disaster without it. The EU barely grows soy and is doing fine. And regarding dust bowl. Those areas of the US have already switched from plowing to no-till decades ago. Another dust bowl is unlikely even with drought because of it.