I'm not sure why you would promote Quora in search results. They lock non-members out after viewing just one or two answers, and the content on Quora is generally viewed as worse than Reddit (not that Reddit is particularly great...).
But at some point (My speculation), answering on Quora became a thing in India. Something that looks good on your resume or something.
After that it went to shit pretty quickly.
The site was inundated with repetitive low-effort questions, often with false premises that seemed intentionally crafted to provoke people. The crappy questions drowned out the interesting ones that had previously made me a regular visitor.