Hello,

The rationale is briefly explained at:
https://bugs.gentoo.org/910363

As gdk-pixbuf upstream is not including support for new formats, people
usually need to manually enable "gdk-pixbuf" USE for important libs
such as libheif, libjxl, or libavif.

At least for Gnome environments, I think that the USE could be globally
enabled as gdk-pixbuf is used everywhere and the dependency will be
installed anyway.

Any issues with enabling it for gnome profiles?

Thanks and best regards