For those who are curious: the Tc is stated as up to 1.7K in the abstract of the Nature preprint (https://www.nature.com/articles/nature26160). This isn’t a high-temperature superconductor.

It’s still very interesting though (as things in Nature usually are). I’m a little surprised no one had looked at electrical conductivity with misaligned vdW epitaxy - it seems like the an obvious thing to look at to me. They’re still using micro mechanical cleavage (ie, peel it off with tape) - maybe it was a cleanliness or size issue? Maybe it’s just easy hindsight.