It's a video game engine. It's got a ton of optimisations and tweaks to make it run in realtime, but if you're making a movie there's no reason not to spend hours rendering each frame. You don't need to optimise meshes at a distance, or use real-time raytracing with noise reduction rather than just simulating a thousand bounces or limit yourself to 4K textures, you can use as many particle effects and simulations as…
Say you're making children's videos like Cocomelon or Bluey in 3D, you don't need all these nice things.
At the end, movies are about the stories, not just pretty graphics.