The bar for conspiracy I think needs to be pretty high.
Perfect example of this is "X." X is some highly mainstream, controversial thing happening right now. "X" has a lot of videos. YouTube starts removing videos of "X". People start to say YouTube is censoring. Maybe they are. However it's more likely that the increased traffic to "X" and the fact that it's controversial results in more people (in aggregate) using built in tools such as commenting, flagging , etc. to highlight the video. Some criterion might be met and high activity videos that are "controversial" might be removed or throttled.
From the outside it looks like a conspiracy. I'd love for someone to post conclusive evidence of YouTube engaged in some conspiracy around these livestreams.