People in TV shows are paid (via the production company) because the TV broadcaster is paid, because it sells advertising during the show. Advertisers pay because the broadcaster can demonstrate that a lot of eyeballs are watching, and they commission programmes that many eyeballs enjoy watching. There can also be direct sponsors, merchandising, franchises, etc.

People in livestreaming are paid because their platform is paid, because it sells advertising during the livestreaming. Advertisers pay because the platform can demonstrate that a lot of eyeballs are watching, and they support livestreamers that many eyeballs enjoy watching. There can also be direct sponsors, merchandising, franchises, etc.