Linux

Yep pretty much but on a larger scale.

1st please do not believe the bull that there was no problem. Many folks like me were paid to fix it before it was an issue. So other than a few companies, few saw the result, not because it did not exist. But because we were warned. People make jokes about the over panic. But if that had not happened, it would hav been years to fix, not days. Because without the panic, most corporations would have ignored it. Honestly, the panic scared shareholders. So boards of directors had to get experts to confirm the systems were compliant. And so much dependent crap was found running it was insane.

But the exaggerations of planes falling out of the sky etc. Was also bull. Most systems would have failed but BSOD would be rare, but code would crash and some works with errors shutting it down cleanly, some undiscovered until a short while later. As accounting or other errors showed up.

As other have said. The issue was that since the 1960s, computers were set up to treat years as 2 digits. So had no expectation to handle 2000 other than assume it was 1900. While from the early 90s most systems were built with ways to adapt to it. Not all were, as many were only developing top layer stuff. And many libraries etc had not been checked for this issue. Huge amounts of the infra of the world's IT ran on legacy systems. Especially in the financial sector where I worked at the time.

The internet was a fairly new thing. So often stuff had been running for decades with no one needing to change it. Or having any real knowledge of how it was coded. So folks like me were forced to hunt through code or often replace systems that were badly documented or more often not at all.

A lot of modern software development practices grew out of discovering what a fucking mess can grow if people accept an "if it ain't broke, don't touch it" mentality.