But this is the other way around; if I wanted to draw a computing analogy it would be arguing that if I wanted to provide massive cloud storage then the physical volume density of information (bytes/m3, a funny but practical measure to talk about) can't approach the density of 1Tb consumer grade hardware.

And that would be true, but it could still be a good target within an order of magnitude, because it could be set up as a very big RAID array. There would losses due to cooling and power and space between the drives and whatnot, but to a first approximation (Facility Volume / 1Tb density * 50% fudge factor) will be pretty reasonable; especially if someone really tried to engineer clever heating solutions.

So the paper gets (checks) ~1,300t/ha lab conditions. Why, in theory, can't they just replicate the lab environment as many times as fits in a big facility? I can see practical impediments like cost, I can't see theoretical ones if it is decided that This Must Be Done. I'd expect reasonable yields of 650 t/ha. That improves on 17 t/ha farming practice [0]. Point is that sort of calculation is totally routine when looking at academic results and I don't see what the problem is using a 3'x3' lab environment then extrapolating with a fudge factor.

[0] https://en.wikipedia.org/wiki/Wheat#Yields

No need to speculate, just need to try :) Everyone just needs to share their results and let the risk takers and builders do what they do best. If they fail, in this scenario, the only thing wasted are time and money, and the only thing gained is knowledge.