[cleancoder0]

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6893534/

This review debunks the "bioavailability" and "quality" claims quite easily.

"bioavailability" (pdcaas diaas) is a contrived measure of protein source completeness made up to characterize protein issues of starving humans. It was also calibrated on rats and pigs, not humans. The "complete protein" misinformation is everywhere. Even on Wikipedia https://en.wikipedia.org/wiki/Complete_protein (edit: now I see that someone recently changed the statement to "adequate proportion" while previously it was just referencing that it contains all 9 essential amino acids).

All plants contain all essential amino acids, including green grass. Completeness in case of no starvation does not mean a thing. If you are eating 3000kcal of wheat every day, protein is no longer a worry, despite wheat having a 25% made-up bioavailability measure that was deduced by checking what happens to nitrogen in a live pig.

The protein "concentration" is just not true. Chicken breast does not have 90g of protein in 100g of chicken breast. 35g of protein in 100g of raw soybean. You will have to find a really rare steak of 100g to top that.

> Many ex-vegans have been consistently anemic, even while taking iron supplements, until they re-introduced meat.

This is not at all the conclusion of peer reviewed articles. Increased occurrence of nutrient deficiencies in vegan populations does not exist. Some people get deficiencies on any diet, and this is also the case for diets that have low-calorie high-volume foods like plants. Nothing special about that. People need to eat more volume but rarely do so. Similarly, they need to eat more calories. Talking about micronutrients in a world with no starvation is unnecessary. If you're eating a variety of plants, enough calories, it is certain you are consuming all of the necessary nutrients and protein. If you want to do powerlifting, marathon running, you will need to adjust your diet, whatever diet it is.

[humanrebar]

I think you misunderstood the protein concentration concerns. People are concerned about the ratio of calories from protein to calories from other macronutrients. In the case of beans like edamame, the concentration of fiber becomes relevant as well.

In contrast, chicken breast is nearly entirely calories from protein and very low fiber. Replacing some chicken breast with soy makes sense, but your fiber budget would cap out quickly and that would leave no room for other fiber rich foods like fruits and leafy green vegetables.

[cleancoder0]

There was an explicit mention of protein quality and bioavailability. Both terms are standard and widely used. If OP meant something different by these terms, then fine. There's a minor loss of protein that is trapped in fibre for most plant foods that humans eat.

There is small amount of fiber in tofu, seitan, tempeh or other soy derivatives.

The "protein concentration" was mentioned together with iron, as if it is a problem of deficiency, not in the context of obsessive compulsive dieting by tweaking your macros to achieve the best results.

I am not sure the fiber budget you mention is a reality. There is no threshold where your body will stop behaving if you consume too much fiber.