Y2K, from both sides. The misconception is picking one end or the other, that it wasn't a problem or was a problem worth panicking over. It was in between.
We can measure whether we overspent, or didn't spend enough, in fixing Y2K: just compare the amount spent vs. the costs on 2000-01-01 of unfixed problems.
If we'd spent $10billion, but the remaining unfixed problems caused $100billion of damage on Jan 1, 2000, then it means we didn't spend enough. What really happened, though, was we spent $100billion fixing it and remaining unfixed bugs caused less than $1billion damage.
Yes, risk analysis has huge margins of uncertainty, but we can still measure things. The measurement of Y2K is that we overspent fixing bugs. There was still grave problems that needed to be fixed. If we'd done nothing, the costs probably would've been enormous.
We can't say what the proper amount would've been, as it's a non-linear relationship. But we can say with confidence that we overspent.
But in any case, these tweets are about nuance, which isn't allowed these days. The in between position that it was a grave problem, but we spent too much, isn't allowed. The only two allowable positions are it wasn't a concern at all, or it was worth the panic.
