There is nothing more insidious and anti-free speech than claiming that someone else is required to provide you the soapbox to stand on.
Saying that Youtube or anyone else must pay to provide a platform for someone else is as about not free as you can get. I don't' care that their big or that it gives them market power. Your right to free speech ends at your nose, no one else is obligated to help you speak. You are literally demanding that these companies provide the soapbox at their own expense and that's wrong in so many ways and you probably don't even realize how evil that suggestion is.
If you think there should be a platform where anyone can say anything and no one can take it down then you should support the government building the platform, not forcing some private company to provide the soapboxes and pay for it all.