Perhaps instead of censoring the song, YouTube could require that the uploader include at the end of it an explanation of what it means for a pandemic to not be "real". Does it mean that COVID doesn't exist, and people are just pretending to have symptoms? Is that what "they" planned?

By actually getting people to talk through their beliefs, and state them clearly, society might be able to consider all opinions and have a conversation, rather than accepting the idea that our technological gatekeepers can be trusted to evaluate them correctly on our behalf.