Many YouTubers and many Twitter users would say more conservative things, but Google and Twitter actively discourage and ban users in a way which is pointedly biased. Some of those so targeted deserve such treatment. However, not all of them do. Many of them are simply in ideological disagreement.
It's a dilemma. If monopolies and near-monopolies are allowed to use corporate power to police speech, then this is allowed in the letter of the law, but it stinks to high heaven as far as the spirit of free speech goes. On the other hand, the government shouldn't be in the business of policing speech.
The way out of this dilemma is to break up near-monopoly power where it exists. Right now, there really isn't a good alternative to YouTube, and this near monopoly power lets them effectively police speech across the entirety of a certain kind of widespread culturally relevant media: That of personal video commentary.