Moreover, in legumes and cereals the proteins are mixed with large amounts of starch and if the proteins are separated from starch in industrial processes the cost of the protein extracts is many times higher than the cost of chicken meat.
Only wheat flour is an exception, because the gluten from it can be extracted without special equipment or chemical substances, so wheat gluten is the only source of pure proteins that I am aware of and that is cheaper than chicken meat.
Fun fact, for octopuses that number is 3x, which (not that I've researched it) is the most efficient number I've found.
https://animals.howstuffworks.com/marine-life/octopus5.htm#:....
The question of scale and costs is a really good one. I suspect the real savings will not be in growing a chicken but in the whole logistics of getting a chicken into a supermarket packaging for you to buy. The process of taking a chicken from farm to supermarket is highly labor intensive and while it scales unit costs don’t decrease meaningfully with scale. The cultured meat decants ready to pack and could be packed and shipped in a fully automated fashion that decreases in cost as scale increases.
I personally doubt this is anywhere near being able to compete with real chicken. Chickens are one of the most cost-effective sources of protein.
https://ourworldindata.org/grapher/energy-efficiency-of-meat...
To put it into perspective beef requires 50x more energy input, than caloric output. Chickens only require 7.7x more input than caloric output, eggs are 5x.
Chickens take in corn and produce fat and protein. I'm unsure of the number of steps for lab grown meat, but I doubt it'll be fewer steps and likely will have more chemicals (and likely be less healthy).
That said, I wouldn't be surprised if they add regulations and additional burden on the non-lab grown meats and subsidizing lab-grown meats (they effectively do already subsidize it through grants).