Well you have to remember that they are a fairly small team at Bethesda Software, so by the time Sky UI was stable they had probably moved on to another project and didn't think the work necessary to change the UI was worth it. It is fairly easy for us to think it would have been a simple task to get it working, but changing something as intrinsic to the game as the UI can often have major knock-on effects on other areas of the game.
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