Hard to say what the takeaway or lesson is here, other than having trustworthy professionals disseminating unbiased information is a public good and losing it creates paranoia and social distrust everywhere.
I think this is a silly claim of a very complicated topic. Our ability to trust various institutions (e.g. the newspaper, government, banks, markets, pollsters, academia, tv experts) in both their expertise and morality obviously has varied over time and by country. Some of it we obviously have lost (at least temporarily), e.g. trust in the US government, some other areas remain strong.
This situation of having entirely fabricated poll causing a candidate drop out of a race was not on our radar (obviously, or else McMorrow and her doners would have waited for more than 1 poll). Therefore it represents a reduction in public trust with negative externalities beyond just this one race.