If I look on the explore tab on youtube, the content they are actively promoting, it is a lot of mainstream entertainment and sports content. I also agree that they have done way more than twitch to make themselves advertising safe. But there are a lot of popular channels on youtube which are independent and not run by established companies. A lot of those channels are very edgy, and it is even a relative safe haven for people who were considered too hot for twitch and banned, but they face a constant struggle with being demonetized or not recommended, which is a less publicly visible moderation tool than the twitch ban.