Set Camera icon per script

It is great that since 3.4 it is possible to manually select an icon for any GameObject. However, I would like to do this by script. OnDrawGizmos() works well if the object you want to apply your icon to does not come with a predefined one.

But what about, say, a camera? If you change the icon in the inspector by hand, it works. If you use OnDrawGizmos, both your defined icon and the default camera icon show up. I don't want to change dozens or even hundreds of camera icons by hand, so is there a way to do it by scriptand hiding the default one?