Assuming that 25 kg of grain/soy is needed to make 1kg of meat (just picked a number from a poster here), are you really sure that 25 kg of grain/soy is better

Assuming that 25 kg of grain/soy is needed to make 1kg of meat (just picked a number from a poster here), are you really sure that 25 kg of grain/soy is better nutritionally than 1 kg meat ?