People usually have a reason for disabling comments, like if they get too many and it's overwhelming (that's usually the really popular people), or they don't like getting comments, or something like that. I personally love getting comments and I like commenting but I usually just fav and run xD
Sometimes, I want to leave comments, so I'm slightly annoyed if they're disabled. But logically, I can understand (or even know) why they're disabled, so I quickly move on from being annoyed to just moving on.
Sometimes I don't mind it, and understand that theres reasons. But there are other times I want to cooment on the picure but can't since the comments are diasbled. Cooments are one of the best way to show what others think of the picture especailly with giving tips on what you can do better.
Sometimes, something really moves me and I like being able to say thank you or that it was beautiful or how it affected me. And I personally LOVE getting feedback no matter what it might be. So I wouldn't disable comments, but that's just me.
I like to give comments and recieve them, afterall it's a community where we share praise & criticism alike, so I think comments should always be enabled, unless it's a touchy subject that will attract the do gooders & trolls