No I'm pretty convinced. That quote wasn't my only source of info. Here's some that I pulled off of another website. A lot of info here. Scroll down half the page for soy (reposted below).
Avian Natural Veterinary Care and Bird's Optimum Nutrition
The health claims of the soy industry have one purpose and one purpose alone - to sell more soy! That's why you'll only hear about the benefits of soy from the industry, but Soy Online Services thinks all consumers deserve the right to make an informed choice about what they are eating and feeding to their children, their household pets and their livestock.
Soy Online Services found a wealth of evidence that the soy toxins cause both acute and chronic effects in both animals and humans. The industry refers to the soy toxins as 'anti-nutrients' but, in fact, they are classed with environmental toxins and they are present in every food product that contains soy. As often occurs in cases of environmental poisoning, Soy Online Services first became aware of the toxicity of soy because of its effects on animals. The harm that soy causes animals has been known for decades, but this fact currently appears to be ignored by manufacturers of animal feeds who are ever eager to utilise cheap sources of protein in their products. The use of new generation bird feeds that contained soy coincided with thousands of bird deaths and disorders. These effects were widespread and were reported by many of New Zealand's leading parrot breeders:
* beak and bone deformities
* goitre.
* immune system disorders.
* infertility.
* premature maturation.
Bird breeders noted that a common factor in the diets of affected parrots was soy protein. But could the effects seen in parrots be explained by the presence of the soy toxins? Soy is high in phytate, which reduces mineral bioavailability. Upset the delicate mineral balance in a parrot's diets and bone and beak disorders are the result. Soybeans contain high levels of phytoestrogens. Although investigators didn't know it at the time, the compounds are powerful immune-suppressants, potent goitrogens (the goitrogenic effects of soy products are even discussed at length in the text 'Diseases of Caged Birds' - TFH Publications, 1988) and as the name suggests, able to elicit estrogenic effects. Strong candidates then as the cause of the infertility and premature maturation. (see pictures of premature maturation of Juvenile (green) and adult (red) Crimson Rosellas)...