No, not really. The browser setting is for default _font_ size for a reason. People want legible text. Design elements like icons, pictures, margins are general

No, not really. The browser setting is for default _font_ size for a reason. People want legible text. Design elements like icons, pictures, margins are generally decorative and not functional. If a user wants to set a default _zoom_ level, then they can set that as well. As I said, these are two different things.