The most consequential Excel error was The 2010 Reinhart-Rogoff error in the paper "Growth in a Time of Debt" https://www.nber.org/papers/w15639 The paper claimed that average real economic growth declines 0.1% when natonal debt rises to more than 90% of gross domestic product (GDP). When you correct the error it shows 2.2% average increase in economic growth. Paul Ryan used it in the US for Republican budget proposa…
I think you're overstating both the paper's impact, and the significance of the error. Most such papers are used to support existing policy preferences, not drive them. In addition, the error didn't reverse or erase the correlation, it diminished it, and removed the inflection point from the curve.
Krugman [0] called it "surely the most influential economic analysis of recent years" and adds that it "quickly achieved almost sacred status among self-proclaimed guardians of fiscal responsibility; their tipping-point claim was treated not as a disputed hypothesis but as unquestioned fact."
However, indeed, he cautions that "the Reinhart-Rogoff fiasco needs to be seen in the broader context of austerity mania: the obviously intense desire of policy makers, politicians and pundits across the Western world to turn their backs on the unemployed and instead use the economic crisis as an excuse to slash social programs. What the Reinhart-Rogoff affair shows is the extent to which austerity has been sold on false pretenses."
I'd say the paper made it certainly easier for the Very Serious People[1] to push through their austerity agenda.
[0] https://www.nytimes.com/2013/04/19/opinion/krugman-the-excel...
[1] Krugman's derogatory term for duplicitous policy wonks (like Paul Ryan) that pretend to be thoughtful and serious and concerned about the nefarious long term effects of debt when discussing stimulus and spending and social programs, but then typically turn around and implement huge tax cuts without second thoughts...