What? Y2K did have many demonstrable problems... Having a 2 digit year did obviously cause problems. The reason nothing happened is because a shit ton of time and money was spent making sure it didn't.
The latter is just a ripe plumb, left to rot in the backlog.
It was thankless work that is still glossed over and waved away today, but it was all a very big deal throughout the late 90s.
Mike Judge even made a movie about it! Office Space might be the most recognition turn of the millennium programmers will receive.