Traditional marketing is dead. No one likes ads. But the amount of people watching game streams? Enormous. Slay the Spire is the typical tale of how streaming sparked a deck building gold rush and it started when a streamer played a few hours and got some word of mouth going.
Marketing is still a very viable approach to figuring out how to sell a product. But ads themselves are actually poorly regarded and when folks are given the option of how to receive retail information, they don't want unstoppable messages for things that don't appeal and will never be purchased. And it sours the brand to viewers who have to watch.
But getting some charismatic people to have fun with your product? Guaranteed to get some eyeballs who are willing to be there. That's what ads will start to look like: appeals to friendship.
Marketing is still working but unskippable billboards on the gates of our entertainment are dying off.