Two thoughts:
1. YouTube is a for profit company, users naturally use their channel to profit themselves. They are not obligated to commit to free speech, although I would argue that if they can find a way to make that profitable over the long term, they should work towards that goal as that would ensure their business's longevity.
2. Internet culture has devolved into an ugly place where posters feel free to anonymously slag and troll as viciously as they feel entitled to, that said IMO policing one's comment section to dissuade the trolls is a very difficult exercise in walking fine lines, I don't envy anyone with a YouTube channel they are relying on to pay the bills.