There is no rational explanation that justify why a really major issue, or for that matter even simply an issue most users want, should not be implemented by the core developers for 6 freaking years. If you are too busy to code, you should step down and leave the position; same thing if you think the bug is not one of your personal priority: you are the maintainer and you have taken up a responsibility towards the users. Abandon if you cannot do it.
I had my own little delusion with nautilus developer, of which I talk here ( http://gilest.ro/2011/patches-for-nautilus-move-to-trash-bug... ). Same attitude there: lots of people want the bug fixed, patches exist, won't fix.