Limit icon file size via quality setting in Preferences?

[pond]

A Mac App Store reviewer writes:

Perí – Mar 14, 2017
My original jpg file is 1000 x 814 pixels. It weighs 70 Ko. But the created icon weight is 900 Ko. I am quite sure that the ICON format is not compressed but I would appreciate that Add Folder Icon would down sample the model.

This is a good point; retina icons reach 1024x1024 pixels, but how often do people set their Finder to display such large icons? I've written in response:

That's quite unfortunate - yes, as you guessed, the icon format the Finder requires is not compressed. We also have to make icons all the way up to 1024x1024 pixels in the era of high density Retina-display images, which can lead to some pretty big files.

I've added a feature request to the issue tracker for Add Folder Icons which suggests a user-selectable option to reduce large size icon quality as a trade off for smaller icon file sizes. Very few people have their Finder icons set to very large sizes, so for many users this could represent quite a big saving on disc space and have no visual impact.

This issue tracks the request.