“On 8 February 1999, while testing Y2K compliance in a computer system monitoring nuclear core rods at Peach Bottom Nuclear Generating Station, Pennsylvania, in

“On 8 February 1999, while testing Y2K compliance in a computer system monitoring nuclear core rods at Peach Bottom Nuclear Generating Station, Pennsylvania, instead of resetting the time on the external computer meant to simulate the date rollover a technician accidentally changed the time on the operation systems computer. This computer had not yet been upgraded, and the date change caused all the computers at the station to crash. It took approximately seven hours to restore all normal functions, during which time workers had to use obsolete manual equipment to monitor plant operations.” https://en.m.wikipedia.org/wiki/Year_2000_problem https://en.m.wikipedia.org/wiki/Year_2000_problem We do not have a full list of problems that were averted. The only way you can state it was overblown is if you know what would have happened if we hadn’t fixed all the systems. There were definitely countries that didn't do much and had very few issues, but that doesn't prove that e.g. the far more computerised West wouldn't have had. The only rational course was to check every system that the failure of which would cost more than checking it. It was insurance against a problem that had unknown levels of downside until the work was done.