Unfortunately it would be impossible to outright ban conspiracy videos, and to make things worse, YouTube seems to be recommending them as well, although unintentionally. However the good news is that YouTube is finally doing something about it and has announced that they will stop recommending such videos in the future.
According to YouTube, “To that end, we’ll begin reducing recommendations of borderline content and content that could misinform users in harmful ways—such as videos promoting a phony miracle cure for a serious illness, claiming the earth is flat, or making blatantly false claims about historic events like 9/11.”
YouTube also notes that not recommending these videos does not mean that these videos won’t be available. They state that users can still search and watch those videos and that these videos will remain up as long as they comply with the platform’s guidelines. According to YouTube, “We think this change strikes a balance between maintaining a platform for free speech and living up to our responsibility to users.”