People do care about this - there are a few attempts made to create such mods:
Actual Windows - Farmhouses:
https://www.nexusmods.com/skyrim/mods/5 ... escription (Unique DLs 15,206 Total DLs 29,017)
Immersive Interiors:
https://www.nexusmods.com/skyrim/mods/39208 (Unique DLs 70,975 Total DLs 131,239)
And Pfuscher attempted with cubemapped windows a year ago:
https://www.nexusmods.com/skyrimspecial ... ideos/5215
All these mods cover just a small portion of the game and have their own problems.
And there are also two fundamental problems with such mods - 1.) there are actually quite a lot of windows in the game and they need to be done one by one.
2.) These mods don't work on new or modified buildings - which are countless.
The only realistic way to do this would be something that detects every possible window and applies some texture to them. Inside and outside.
That brings us to the ENB.
No need for a time of day - if this texture or cubemap could be tied to the windowlight parameter. (having both - texture and windowlight)