Yes, my country's traditional diet emphasizes that "grains are good for nutrition, but the absence of beans is bad." This means that grains are nutritious, but without beans, the balance will be lost. Legumes are the health "guards" of the gastrointestinal tract. Eating more legumes is beneficial to the digestion and absorption of the gastrointestinal tract.
Both black beans and soybeans provide high-quality protein and have similar nutritional value. Soy milk contains less oligosaccharides, which may cause less bloating than eating soybeans or black beans directly.