Yeah, but not really

So here is an article about the importance of color and how from minimal poster deigns, these characters are so easily recognizable.

Yes they are.

But I would argue that it is far more from consistency than by color.

By adding the eyes, you know who they are right away. Take away the eyes and you'd relate each color to something from your own thoughts. I thought the orange one was Ernie at first. Because I never paid attention to Garfield.

Yes the color of these characters is a key part of them, but it's just part.

Why these work is because you have seen (two) these characters for as long as you've been alive. And these characters never changed. They did not get a re-branding or an updated look to go with the times.

To me these say… When you have something that works, stick with it. For a long time.