I see no reason we can't have a plant based $1.55 burger that's not superior to the meat burger on all those metrics. The plant burger doesn't have the whole animal portion of the supply chain to pay for. It seems like an economics of scale issue.
I don't know anything specific about how the Impossible meatless burger is produced. I know that there are some tricky economics involved in beef production, specifically in government subsidies for the corn which is fed to cattle to make beef; the stream of meat "byproduct" which is turned into "ground beef"; and the huge supply of land and water rights used for grazing cattle which was obtained long ago by huge ranches for free or cheap, which any new at-scale competitor (meat or meatless) will have a hard time beating.