I don't believe there's such a thing as "no design" design. It makes very little sense to me. There can be design with very simple and efficient flow but each individual interaction can (and probably should) be engineered.

E. g. where exactly to display the text, what should be the copy, how does the text input behave, where is it positioned and how does it all handle potential error, loading or any other state. To define all of these things and more is to design. Simple-looking visuals don't necessarily mean a lack of design.