As a Youtube video editor, my opinions are probably skewed, but I am a fan of youtube as a platform. Long form edited videos allow you to explain things not only with text or voice, but you can use visuals, animations, and hand picked footage. It allows for catering to a wider audience.
That being said, twitch is a community that brings HUGE benefits to the table. Being able to chat in near real time in a small community of people is an experience you will probably never find on youtube. Unfortunately I'm a lurker so youtube wins