Correct, they also have quite a high fiber content.
If my memory serves me well, Soya was marketed quite stongly as a meat substitute and went under the name TVP (Textured Veg Protein). Research later showed that our bodies do not metabolise soya extract very well, and it turns out too much soya is v. bad for us. Not sure how much would be considered harmful (I have seen advice of 30 gms per day in diet articles). Nowadays, i think food manufacturers tend to use mushroom for their meat substitutes in pies, curries etc.
The safety risk may be urban myth. There is a chemical in soya that mimics oestrogen, and one study found that this chemical bound to oestogen in the human body, which may have increased the risk of breast cancer in women and infertility in males. This study has not been confirmed, and no evidence of a link to cancer has been discovered. Tofu is deemed safe, and soya appears in most processed foods we buy today as a low fat substitute and as a carb substitute in Low Carb diet foods, So we are already getting bombarded by it, especially since it reduces manufacturing costs.
It would seem that traditional fermented soya products such as Soy Sauce removes most of the harmful compounds, but modern factory processing creates new compounds. in addiion, MSG is often added to create taste and texture to products, since raw soy flour has a horrible taste and does not form a dough without it
Like i say there is a lot of urban myth about Soybean products, but it was the first plant that Monsanto produced as a GM variant specifically for the USA and Mexico.