WebMD, Wikipedia, CDC, etc. for health results, the NYT, CNN, BBC, etc. for news, major magazines/newspapers for reviews. Which makes sense from a corporate perspective, you don't want your users searching for something controversial and stumbling upon something that doesn't line up with the mainstream POV. Maybe "Bob's 10 best mattresses" is a thorough and exhaustive article that easily beats the rest, but what if Bob is antivax, or thinks Bush did 9/11? It's safer to just ignore small blogs like Bob's and not risk any controversy.
And here's the side effect. Some of these organizations realized "Wait, we rank really high on Google for anything! So let's pump out shitty listicles about the top 10 air purifiers, even though we're a tech company, and fill them up with expensive affiliate links. We're 'trusted', after all."