Diane, I believe I am being misunderstood. Sure, I have days when my hair isn't singing. Just like I have days when my pants proportions are off. I'm talking about general styling feedback, not "Dang your hair looks like crap today" comments. No one says it about a shirt, nor would anyone put up with it should someone say that about anyone, outfit or otherwise.
If you scan up, you'll see I'm mostly talking about styles... Suggesting someone put up their hair, or try bangs, or light layers, surely isn't that different from saying you'd add a belt, is it? Yes, it's attached to the body, but it is morphable! And it can make a huge difference to an outfit, as we all seem to agree. I don't believe this is over-scrutinizing. This is a style/fashion forum.
And I disagree hair is different than clothing, we all know photos don't represent an outfit in motion and we comment there anyway.
The general consensus, however, seems to be that hair is off-limits for comments, so I will continue to refrain from commenting unless asked.