If they were blown out, though, then their light would spread well beyond the window frames and obscure a fair portion of the image around them.
Not necessarily. I used the term "blown out" in the general photographic sense of overexposed. I can shoot a night shot of a building and expose it so the moon, stars and sky glow make the structure visible and the windows are lit brightly enough that you can't make out interior details -- only brightness; yet the windows don't bleed over enough to obscure the building. Why nit pick what was merely a casual suggestion that could help what we saw onscreen make a bit more sense?