I think this is a false dichotomy. There is a difference between freedom of speech and freedom to use the most popular communication service. Just because a communication service is popular, does not automatically mean that everyone should get equal access. Freedom of speech means that you are free to say what you want. You are free to publish what you want. It does not mean that the most popular distributors of information a forced to carry your message.
Going back in time, it means that you are free to write a book. You are free to print the book. You are free to distribute the book. You are not free to demand that the most popular bookstore must carry your book. Neither does it mean that the most popular newspaper must publish serialised versions of your book.
It also doesn't mean that you must have equal access to the most cost effective means of distributing your message. Even though the news paper (in times gone by) reached every house and syndicated stories could travel the world incredibly efficiently, it doesn't mean that they are forced to syndicate your story. They have a choice. It may be true that you can't afford to send information to practically everybody in the world like the wire services can do, but that's just too bad.
These days because communications are so cheap to be practically free, people often thing that they should be entitled to the best delivery mechanism possible and that everything else should be considered censorship. A private entity choosing not to spread your message is not censorship. It's a choice and it's a choice that every private entity should be able to have.
I'd rather have the freedom to choose even if it means that tons of people do not have access to the most popular and efficient means of spreading their message.
Of course, if there are groups of people colluding to block your message, then that might be a form of censorship. If you have Youtube making deals with ISPs to make sure that you can't host your own content, etc, then I think that's a problem. That's the kind of action that only governments should be able to take (and with the correct oversight). But people and corporations should have the right to choose what business they want to engage in unless it impinges on special categories that we have already marked for protection (and insane consipracy theories are not marked for such protection).