I've been relatively convinced that, in the absence of some very major tech breakthroughs that are not even yet on the horizon, lab grown meat will not make sense except in extremely niche applications, perhaps even to the extent of it only being a thing where rich people buy lab grown versions of endangered/extinct animals.

Modified plant proteins like Beyond Meat and/or the kinds of organisms you describe seem to be a much closer, easier, and more likely near-to-medium term solutions. And I say that as someone who would love nothing more than for lab grown meat to succeed and someone who has made a variety of sacrifices and to both eat less meat and when I do eat more sustainable and ethical meat (to the satisfaction of my own personal morals).