I don't think they will need to judge you with anything after this. Doing this one thing beautifully will land you a job. Plus, you will have a project to show off in the next interview.
That doesn't mean I don't understand your POV. It is just a matter of perspective. I understand yours, just start thinking optimistically. This is just one challenge for which you won't be paid but could get you either a job or learn you didn't do well on creativity and now you have one more project to show off. Or, you just don't have hunger for a job. Look at the market, you aren't alone with capabilities and rigidness. Learn to be flexible with other POV rather than just shrinking in your shoe.