alt Hacker NewsYes, but the standards aren't based on "the best protein to absorb", they are based on whole diet consumption. Studies like the one I linked to are where the recommendations come from. It is a misunderstanding to read a recommendation for 1.2g/kg (or whatever) as saying that the 1.2g is supposed to all be meat quality protein. It's supposed to be the protein in your total mixed diet.
Your diet contains many sources of protein lower quality than beans (as in the linked study with high level Dutch athletes getting 19% of their protein from bread), you do need to count those. They do add up and if you don't, you end up assuming you need way more protein than you do.
but then how do you know how much protein you should eat ?
if I'm eating bread, pasta and other cereals, I may exceed the 1.2g/kg recommendations but the PDCAAS (Protein Digestibility-Corrected Amino Acid Score) of these would make it in truth closer to 0.6g/kg.
Someone else eating mostly meat would get in total 1.2g/kg protein but also 1.2g/kg when PDCAAS is accounted for.
Maybe it's to simplify the calculation to the average user but it feels misleading, you can't know for sure the proportion of cereals in somebody diet.