So there is a broad consensus? Makes sense. Is there some difficulty or other purpose in not adding the option in that you know of?
Just the usual probably, time and effort required to implement. Even if it will only take 40 hours of time to do, that's 40 hours of people's time not doing something more important.
That 40 hours is not unrealistic. Yeah, its a simple feature on the surface, but there has to be meetings with multiple people to discuss how it would work, which requires at least one code monkey, one manager, and a UI guy. Once its decided how it will work it then has to be approved by a higher manager, and time in the plan allocated. The the dev(s) have to implement the first version (a few hours possibly to implement it, as well as the UI for it), then unit testing by the devs, then passed to QA for checking, possibly back to the devs for bug fixing, back to management for approval for code merge.
Not to mention, even if discussed and approved, the prioritization could be a killer. Its sat their in their bucket list, all specced out, devs can be ready to work on it, but simply no time. They look at the plan for the coming week. "Let's do the colour thing!" Manager: "Nah, not this week. You have to deal with features, X, Y, an Z this week. Maybe next week."
Next week: "Let's do the colour thing!" Manager: "Nah, still needs to be on the back burner for now. Features A, B, and C are your tasks for this week, oh, and QA found a bug in your code for feature X, you're going to have to rework that one. In fact, C is lower priority, yeah, you know, bookmarks, we might have to drop that one for 2.1 now... forums are going to explode when they hear about that, but nothing to do about it, features A and B are more important."
And that is life in the world of software development.