Pixel art also has many advantages from a dev standpoint. It's cheaper, and thus allows for far more variety in graphics. The deadline are also far shorter, ~1 week for several custom animations while a CG could take 3 times that amount, and even worse if you want it semi-animated. If I were to transition from pixel art from CG, forget about semi-monthly deadlines. Also, forget about having several scenes with different positions per update. At most, you're getting one CG per scene with a few variations.
What's worse, you become extremely reliant on one artist and on their own circumstances, whether they're sick, busy, etc... or you go for another artist with another artstyle and forsake consitency, which is usually not very well received.
With pixel art, I've had artists disappearing for weeks, but since it's small and low-details, I can easily ask another artist and nobody would notice the difference. Same for busy periods, where I can just ask a few new artists to do some extras here and there. As a dev, this is a huge load off my back.
Of course, if you're your own artist, things are different, but all I can draw are vaguely human-looking stick figures.