I think the conversation is much more complicated than a side-by-side photo can convey.
As I type this message my laptop screen is leaning away from me, but my eyes are focussed on the indiviudal words as I type them. Occasionally bouncing to the colourful dock at the bottom of the screen. When I'm writing or 'watching' I'm completely unaware of any trapezoid distortion or key-stoning from the display leaning backwards.
Now if I was to take a photograph of my laptop from where I'm sat, and embed it in this post, the distortion would be clear as day versus a display that was perfectly flat to the camera.
A similar effect happens while watching a curved TV. Your eye continually focus on different parts of the image, but never really look at it as a 'whole' - the exception being maybe full screen, edge to edge geometric shapes. A rarity. We essentially 'zoom' with our eyes, focussing from subject to subject. We don't work like a fixed focal length camera lens.
Now turn the TV off and you'll look at TV itself, as an object as a whole, and it's clearly curved... clear as day.
So what I'm badly trying to describe is that it's not a surprise that owners often find them selves 'not bothered' by the curve. Even if it surprises them. I know the first time I saw I curved display in a store I laughed out loud and thought it was the most ridiculous thing in the world. In many ways it still is. But as you watch whats ON the display instead of the display itself I've found I've fallen into the 'not bothered' by it demographic.
Saying all that, the only reason I bought curved was that my buying choice was basically curved OLED vs flat LCD at the time. Given the choice of flat vs curved OLED at the time, I would of gone flat but I've found myself far less bothered by the curve than I thought I would to the point where I'm not actually bothered at all. Would I buy curve if I was doing precise photography adjustments? Probably not, but I wouldn't work on a 55inch+ screen either. Would I buy curve again if it was purely to watch film content? Yes, if the PQ was better than it's flat competitor.
A photo of a curved display doesn't reflect the experience of watching
I will concede that it adds nothing to the experience, but when watching
the TV vs looking
at the display as an object, it doesn't take anything away from the experience either.
On an end note I find The DIEM project fascinating, as it studies our eye movement when watching a film and goes some way to visually explain why I find myself 'not that bothered' by the curve.