I'm glad that you are finding my scribblings helpful! For reference, the article you are discussing is the "eat like a human diet". And, yes, we often recommend eating red meat in moderation and in small amounts. While we don't feel anyone "needs" to eat meat - we feel it is a better alternative than not eating any at all or supplementing with too many other forms of protein. I do, however, understand the religious perspective.
You can certainly be a vegetarian and many people can live very well on that diet. To do so you need a varied diet (not just salads and tofu). Lentils and many other legumes are excellent alternatives to meat and have many positive properties. Soy products are also good, although they should not be consumed in excess as they may disrupt hormone levels. Nuts and seeds such as almond and pumpkin, as examples, should also be included in the diet.
From a Chinese perspective vegetarians often suffer from the effects of eating too many cooling foods which ultimately weakens them and lowers their immunity (spleen and/or kidney qi or yang deficiency). A diet with the right mix of food, some warming spices (tumeric, cinnamon), working in ginger and garlic perhaps, and coupled with any variety of herbal teas and warm soups, however, is very good for the body. Our goal is really to eat like this primarily but to lightly supplement this with occasional consumption of red meat to preserve yang energy levels. Lentils and the other foods listed above can accomplish this as well for those who choose to not eat meat for religious, environmental or personal reasons.