I think the issue is that YouTube wants to be seen as the "creator" for the content they distribute, and therefore, all content must not contradict the brand image of Google.

Alternatively, YouTube needs to put more emphasis and responsibility on the reputation of content creators and make it such that their reputation gains them visibility over time. A creator with 20 years of community determined honest reporting, should be featured more prominently than a channel that is new or has a controversial history.