It happened to me, flying BA back from HKG comes to mind. Actually most of the crew wern't too bothered but one FA was being difficult. I compromised left the blind slightly up, put my hands around my head to act as a shield... and continued looking out of the window. Isn't that why you select a window seat?
That said direct sunlight can be very powerful and offputting. I always try & get a window seat on the other side to the shining sun as you can see better (I'm obviously a POSH type). I seem to remember from my youth that the old BEA tridents had both full blinds & also a filter that reduced the intensity of light. Can anyone confirm this? If so perhaps they should be re-introduced. Does anyone have experience of flying Ryanair which I believe have removed their blinds? I think that I would find it offputting to give the sun shining directly in.
I read somwehere that the Boeing 787 may have windows where the passenger can control the level of level of light allowed through which would be a good thing, but that this can be overridden by the crew - which could be a very bad thing!
I am of the school that believes that the view outside the window is the best form of IFE followed by the moving map. As an aside, shouldn't all IFE systems include cameras looking forward & down as I know that Emirates has. Great for a non-window seat, but it would need to be very HD to rival a window view.