Actors and actresses are still employed because CGI realism is still climbing up the steep wall of the uncanny valley, but mostly because humans are currently cheaper than CGI. But Dall-E and Stable Diffusion already do very good photo-realism and hyper-realism, and I'm sure CGI costs must be coming down. Watch the Robin Wright move The Congress (2013) for one take on where this is going. It's a really fun and surprising movie!