There were even more companies who did nothing and nothing happened.
That was all bullshit and you know it...............
The tech industry warned everyone who had a digital device that their devices would terminate at the stroke of midnight and that never happened either did it?......Sheesh!
That’s because it depended on the applications those computers were running. Many people had nothing to worry about. Anyone running Unix or Linux servers were for the most part fine. Apple Macintosh were similarly OK. Even many people on Windows PCs were going to be fine if their software had been updated, or didn’t hit certain hardware time calls.
The biggest issues came in medical, governments, financial, communication, industrial, and many power industries where IT infrastructure had just "growed" over decades and multiple layers of various language code co-existed on the systems, sharing data and especially manipulation of dates.
This was particularly a problem in financial institutions (calculation of interest?) and telecommunications (mixing of analog and digital) where the mix of technology was truly arcane. In financial, some systems were so hog bound they were tied to a two digit year, not having conceived the necessity of moving into a new millennium, with programmers thinking the problem would be solved long before the time it would be a pressing matter, but budgets were never allocated to address it. In medical, birth years were also often recorded as double digit data because humans can interpolate the correct century, but computers are not capable of doing that without more objective data. Even the Social Security Administration was not prepared to handle people already born in 1900 and those going to be born in 2000 for this reason. They’d already been running into problems with still living persons born in the 1880s and new registrants born in the 1980s. Bad programming had not prepared for the data collisions of the future because the original programmers with limited data space figured their future colleagues would fix the problems when space became less of a problem, but they did not.
All of these issues had to be reconciled to prevent massive data loss… some of those data could have been catastrophic.