That's fascinating and good info.
I'm a little biased. We got a lot of information pushing us not to supplement from health professionals and organizations, and nothing on the risks of failure to thrive or the case for supplementation. We had a calorie deficit no one caught, because measuring breast milk consumption is opaque, and no one talks about low consumption with the same fervor. They should though, it's an issue that drove an entire industry of wet nurses before formula (who were in turn criticised as unnatural in their day). They say breast if possible, but never detail how to tell the difference between just doing the hard work, or just banging your head against an immovable wall.
This inconsistency in advice, even though calorie deficits are incredibly dangerous, and more clearly so,[0] worries me there's a bias against technological development that keeps us from giving advice about both risks (or really much at all about the more important risk here).
[0] insofar as there are conflicting metaanalyses on breastmilk, but the signal is far stronger here, no one is publishing research suggesting failure to thrive is no big deal.