I'm not super familiar with YouTube's policy on this, but apparently they decided to curb what they deem to be COVID-19 misinformation. I completely agree that what these two are doing is spreading misinformation, this is not anywhere in the range of a seasonal flu, the numbers are clear on that.
It's very naive to think that what these two are doing is a good faith attempt to present a dissenting opinion. If someone wants to use this tragedy as an opportunity to launch their right-wing media career I don't think YouTube is obliged to be an accomplice.
As for my opinions being silenced, if I ever yell fire in a theater, or tell people to drink poison laced Kool-Aid, or tell them to ignore this pandemic, I hope I get what's coming to me.