The first (old) one has more detail in the face which makes it more natural. I know they're both artificial, but so is a painting, but they both could convey emotion at different levels depending on the construction. The new version drains away the warmth, which others have mentioned.

I definitely take the first one over the second.
There's a warmth to the first that's lacking in the second.

You’re still a cutie but the black outlining in the first Bitmoji makes your cuteness better defined and more prominent.

I don’t use them, but I prefer the old one in your example.

I like the first one better!

I like the first one

I think the original looked better, not everything needs to look realistic.

I like the first one best.

I prefer the original.

I prefer the original.

I like the original one. The new one almost looks blurred.

I like the top one (old one) better

I liked the cartoon better.

Look how cute the originals are

Based on this, I prefer the old ones.

They went too much 3D 😔

Don't fix something if it ain't broken. They ruined it the first one definitely wins!

In the second one.. it looks like the mustache has slipped down in between the lips.