I didn't realize Zemeckis directed this. That would explain why it looks like a bland live action movie with a thick coat of paint from uncanny valley. I saw the trailer and was depressed that so much money and manpower is once again being wasted on a soulless mocap movie when those same resources could be used on one of the many brilliant animated film concepts that are still stuck in pre-production hell.
Zemeckis makes amazing live action movies. That's the medium he knows, and he's a master of it. Animation is a shiny new toy for him and he doesn't really know what to do with it, and he doesn't really understand which aesthetics work well in animation and which ones don't. Also, he doesn't have an eye for what is good animation and what does not, because he simply assumes motion capture = realistic animation = good animation.