[cas14655]

In itself your statement is accurate: we did not have data that is impossible to have.

In broader context the implication is not correct. We had experts consider long and hard what to do in the case of an influenza pandemic and the consensus for decades had been to disrupt society as little as possible.

This is the WHOs evaluation of NPIs in 2019 (PDF Warning): https://apps.who.int/iris/bitstream/handle/10665/329438/9789...

It says Contact tracing, Quarantine of exposed individuals, Entry and exit screening and Border closures are "Not recommended in any circumstances".

The experts thought about and decided it was not worth it.

[robertkoss]

You don't want to generalise (COVID similar to influenza huh?) if you don't know anything about the virus.

I repeat myself, at that point We didn't know much about SARS2.

[cas14655]

Well, you are right in a way. Contact tracing, masks and social distancing make even less sense for corona viruses which we full well knew in 2020.