Cutscenes work a lot better (more immersive) if they can correctly reflect runtime-defined assets, e.g. your own character with your customizations, gear and clothes, etc, or the dynamic state of the environment in which gameplay was happening: destruction debris, current time of day, and such.

Plus cutscenes get a lot bigger when you’re doing 4k60 and not 1080p30

Cause they want to push the limits and make their engine look amazing. Also, if they research hard enough, in-game becomes nearly as good as video to the point you can’t tell.

One baby step at a time.

Because actors are expensive. Reshoots are even more of a cost if things change.

With this, you just have the character do exactly what you want, when you want, without needing to talk to an agent.

Video doesn't mean with a camera, just pre-rendered.

Because video cutscenes always look crap 5 years later. Easily distinguishable from in-game rendered.

Of course most games don't care about 5 years later, but it still looks crap.

This is a fair point.