"The study did not look at the impact of stories shared by respected friends, colleagues, or family members on social media." Are we looking at a different story?

Also, one of the researcher's chosen sharers was the US Surgeon General - it's not exactly shocking that information was seen as more trustworthy than random AP articles, especially given how dire and sensationalised news coverage of health-related stories is.

16-17% more people said an article was "trustworthy" and "got the facts right" if it was recommended by someone that they trusted. 49-50% of people were still skeptical even then. This doesn't seem to be a dire sociological illness so much as an expected, common sense finding.

Unless you consider the 16% as a block of voters. I don't think any president has ever won more than a 16% margin of victory in my lifetime. Obama clocked in at ~8%, which is considered very, very high.