> serious issues downstream as most researchers and statisticians that ingested the data weren't prepared for receiving noisy data values
They weren't prepared for data that was obviously noisy. The data has always been inherently inaccurate, and folks just chose to ignore that previously
No, there are dozens of articles discussing the mechanism and explaining the impact it had in different areas e.g. [1,2,3]. And the release mechanism wasn't just "add noise", far from it, you may read the original paper [4] to see how intricate it was, anyone wanting to make real use the resulting data would have needed to understand that approach in detail to work with the resulting data. The report of the national academies [3] is probably the most comprehensive analysis of the mechanism and the complications it introduced, so writing "it has always been inherently inaccurate" is just wrong, this new mechanism was way worse than just introducing unbiased sampling noise.
1: https://www.aeaweb.org/articles?id=10.1257%2Fpandp.20191107&... 2: https://www.science.org/doi/10.1126/sciadv.abk3283?utm_sourc... 3: https://www.nationalacademies.org/read/27150/chapter/14
4: https://hdsr.mitpress.mit.edu/pub/7evz361i/release/2