[Someone]

I would think the overlap between Rosetta 1 and Rosetta 2 is effectively zero, even when including engineers who worked on both as “overlap”. It’s 16 years ago, and Apple bought significant parts of the original Rosetta from a third party that now is part of IBM (https://en.wikipedia.org/wiki/QuickTransit)

So, I wouldn’t use the quality of Rosetta 1 as an indicator for the quality of Rosetta 2.