The first rule of using Reddit for research, is that you don't tell anyone you are using Reddit for research.

Implementing a feature like this will turn Reddit into an astroturfed, SEO hell. There are already articles of people spending a few hundred bucks to make BS go viral on that site.

This can happen more invisibility then an old-school forum (glad Brave is including those BTW), since this unnatural behavior can be easily identified, because of the smaller community, and site that isn't based around upvotes.