This seems like a very generalizing claim, do you have evidence for it? The AlphaGo paper in Nature ( https://www.nature.com/articles/nature16961 ) also has less than two months between submission and acceptance.
I don't know of systematic research on this but it's consistent with what I've seen in the fields I've worked in (linguistics, psychology, geochemistry). The AlphaGo paper was special because it's a super-hot high-profile topic and the journals don't want to get scooped (remember Nature is in competition with Science, PNAS, etc. for eyeballs). However exciting a conclusion may be for psycholinguistics, it won't get fast-tracked in the same way.
another comment provided a good explanation (see below), now it remains to check the editor
"Conflict of Interest Disclosures: Dr. van Dam received a research grant from the Nestec Company. No potential conflicts of interest relevant to this article were reported."
Guys, Nestec own the world's biggest coffee machine company, Nespresso.