https://en.wikipedia.org/wiki/V-2_rocket#Assessment
I think what the article is saying is that there was an awful lot of technical knowledge between the scientific understanding (e.g. talking about what Heisenberg did or didn't know) and being able to build a factory. This knowledge the allies also didn't have at the beginning, of course.
And engineers tend to be less colorfully interesting than physicists. (No offense intended, I'd include myself in this characterization)
We're under fire! Yeah - under fire!! Those five thousand ships the Allies couldn't possibly have, as you say - they've got 'em! Yeah, they've got 'em!! - Major Werner Pluskat, June 6, 1944.
The process used was very crude, simple and inefficient so they needed to do it on a huge industrial scale. And only the US could do it on that scale.
You could call it "the dumb luck of nature" that something like an atomic bomb couldn't have been produced with, say, 19th century technology but that it could, barely, be produced by the full industrial might of a mid-20th century nation.
Which is to say that start-up producing amazing things in basements now certainly rely on the sum-total of previous industrial achievements, we don't how much some interesting bit of knowledge compared to those achievements could be leveraged.
If Wikipedia is to be believed, the US produced more M4 chassis (all vehicle types) in 1943-alone (21,231, admittedly a huge surge in yoy production) [1] than Germany produced of any single chassis type during the whole war (most numerous: Pz III at 15,747 total) [2].
[1] https://en.m.wikipedia.org/wiki/American_armored_fighting_ve...
[2] https://en.m.wikipedia.org/wiki/German_armored_fighting_vehi...
I found this article to be very interesting. The point above in particular, for example, has parallels with the allied code-breaking efforts, which were similarly organized primarily as an industrial operation. (The Bletchley Park data base lists more that 10,000 people who were associated with work there during the war). As with the Manhattan project, much is written about key figures, like Turing and Flowers, whose contributions were of course crucial, but the true genius of the effort was the fact that the British, and later the Americans, created a large industrial organization for code breaking.