Live content has lots of downtime and dull gameplay moments. It can't compete with polished, edited videos - except in the one area it shines: human interaction. That works better when you can see the person. So most streams feature a person or at least an avatar, while edited videos often place a higher emphasis on gameplay. Each format is simply playing to its strengths. The ones that don't you rarely see because they're buried at the bottom of page 726 with four views.