For me, I think it actually works well as a user interface.
If I'm in a mood to be charitable and particularly open-minded, I can choose to squint closely or highlight with mouse, and read a greyed-out comment.
However, once that reading is done, the fact that it's greyed out means I don't feel the need to respond to it, correct it, etc. I know that it's being hidden, that people will give it less credence and attention. Plus, I just don't have to look at it once it's no longer highlighted.
In effect, greying out text is a gentle reminder to "don't feed the trolls"
If I'm in a mood to be charitable and particularly open-minded, I can choose to squint closely or highlight with mouse, and read a greyed-out comment.
However, once that reading is done, the fact that it's greyed out means I don't feel the need to respond to it, correct it, etc. I know that it's being hidden, that people will give it less credence and attention. Plus, I just don't have to look at it once it's no longer highlighted.
In effect, greying out text is a gentle reminder to "don't feed the trolls"