Lots actually. Just like Edision found 999 ways not to make a light bulb. We also learned (re-learned) that common sense is not so common, and that people are just really not into being told what to do.
>Events like this are rare enough
Things that used to be "rare" are occurring more frequently to be considered "rare". Maybe more into the area of "uncommon". The Texas grid example is something so stupid to have allowed to happen after it just happend 10 years prior and with a simple (yet expensive-ish) solution. COVID-19 has had warnings of its level of spread for years with SARS, bird flus, etc. Those in charge of disaster prevention/recovery have failed us.
To me this was all "boy who cried wolf" stuff. I certainly remember media fear porn about SARS, about the expected severity of the next upcoming flu season, etc. It never amounted to anything significant in reality.
COVID has caused three million deaths and counting, with widespread disruption to society. How could you look at that and say the reaction in 2003 was overstated?
Also, the widespread disruption to society has virtually all been from the lockdowns, not the pandemic.
There won't be any lessons learned because in 20 years there will be a more pressing need for something else, and slashing funds for pandemic prevention will be a quick way to win some votes. This pattern will never stop repeating because it can't.
I don't think pandemic monitoring and response preparation are a that expensive, even if you use them just once a decade or two.
And lots of failings highlighted by the pandemic are of a general nature concerning infrastructure debt. If health care wasn't run at max human capacity for "cost effectiveness" we may not have to talk about triage. If broadband internet access and digital literacy were a thing, WFH would run more smoothly.
Even something as basic as having a national stockpile again, learning that we should have a decent manufacturing base for these kinds of critical items, and all the lessons about how to communicate with the public regarding health recommendations. There's plenty to be learned.
Another thing is that we should have more explicit goals. Fauci is still not giving an explicit answer and pretty much just says that we'll just know when to go back to normal. Then they wonder why there is vaccine hesitancy.