A lot of the points here seem to revolve around the physiology of animal cells. All the "extra" energy that's supposedly being saved by lab-grown meat is what's used in real animals to do things like drive the immune system, maintain boundaries around cells that lack walls, regulate growth and toxin removal, pump oxygen, etc. An "efficient" approach is impractical to scale with animal cells, because of the unrealistic cleanliness and nutrient purity requirements of growing animal cells without any of these things.

I think the article's main point is that a breakthrough is unlikely to come from the usual culprits when it comes to economies of scale (larger tanks, greater nutrient production, etc.). Indeed the smaller scale operations are the only ones that seem likely to be able to sell meat at realistic prices in the near future. Something would most likely have to be done at the level of animal cell physiology, and we have no real idea of how to do that while still making what we're growing "meat." And none of the companies involved seem anywhere close to an idea that should work--not even a promising approach that hasn't been tested yet. It's essentially further from reality than something like energy positive fusion is, something that gets treated with great skepticism every time there's an article about a breakthrough posted to HN and which depends on government and university funding for grants--yet we're treating it as though it's imminent or inevitable technology, and investment funds are pouring billions of dollars into these companies as though they're expecting to see returns on investment relatively soon.