That's when you just go animated because they're better off that way anyway. We're probably less than 20 years off from being able to show fully virtual films that are close to being virtually indistinguishable from live action anyway.
When you see one of those "behind the scenes" comparisons of a modern superhero movie with what's shot "live" and what's composited in later, you realize how much of it really is a fancy "cartoon". So much of what you see is animated in some fashion that the main difference between that and something billed as "animation" is the art style and toolset.
