User-specified print settings in GTK applications are silently overriden by system printer defaults and/or just have no effect

I originally posted this issue to the GNOME Settings forum, but I think it may be more appropriate here or perhaps needs attention in both places.

Here is the original post: gnome-control-center#2463

I re-opened this issue because the workaround I outlined is not really a proper solution. The issue begs for a definitive solution that would presumably involve identifying the root cause and devising a remedy by GTK+ developers/maintainers, CUPS developers/maintainers, and/or others.

When searching for a solution earlier, I came across a handful of forum posts, scattered over a span of several years, that seemed to describe the same problem, but there was never a solution provided.

Even in our single organization's use-case, the workaround proposed would require a significant amount of manual intervention on many different workstations, each of which uses a range of different printers, depending on location.

Identifying and remedying the root problem seems like it should be a priority, given the problematic nature of this issue related to basic printing and the persistence of this sort of problem over many years, as evidenced by unanswered forum posts and appeals for help by different community members over the past several years.