I haven't found a detailed study of this, but here would be an example. If people shared a site that talked about the dangers of global warming, but wasn't peer reviewed, does this increase awareness, or does it actually give more credibility to global warming denial sites, since they are on equal footing, both being non peer reviewed? A global warming denialist argument is that a debate still exists (it doesn't), which has been good enough to cause skepticism and lack of action.
I know sites generally have incentives to get their articles or videos shared, so they would rather make their own summaries of scientific results, rather than just link to proper references. But pseudoscience sites can also reference peer reviewed sources, they just give their own interpretations of them. But why should anyone believe one site over another, since the standards for credibility are gone (which all of these sites perpetuate, pseudoscience or not)?
Or is it the case that non peer reviewed sites draw attention to issues in a way peer reviewed sources don't, and while there may be some collateral damage with lowering of standards, people are being swayed by pseudoscience sites either way?
So the main question is, has sharing non peer reviewed sites caused more damage than good in combating pseudoscience (including this site)?