Dreaming of trolls on youtube is common. If you post videos on youtube, instagram or tiktok, you may have attracted negative attention from users who are trolls. These trolls might post nasty comments to attack social media users, to influence them negatively into leaving the platforms.
If you have encountered trolls on youtube or other media platforms, this may trigger dreams. You are aware that competition and jealousy can attract negative comments meant to disrupt activity.