Reading the article, it seems like the intent of this technology is much more geared toward manufacturing supply chains, rather than saying "this part came from John Doe's Ender 3". As many people have pointed out, consumer/ hobbyist grade 3D printers aren't nearly consistent enough to produce anything resembling something as unique as a true "fingerprint", and when you consider that most printers are modified in some way... There's just zero possibility of it being used in that way.

The only way I could see it being used in that way is trying to prove that this printer printed this part; if they have the printed part, and it hasn't been post-processed at all (sanded, treated, etc), they could reprint the same part on the printer in question and see if it's "fingerprint" is the same. But I'd be pretty surprised if this tech could even reliably say, "this part came from an Ender, this part came from a Neptune, and this one from came from a P1".