The author of a comment can tell if it's been upvoted - no one else. I really wouldn't like to see comment threads full of posts similar to yours; it lowers the signal:noise.
Obviously it would be terrible if everyone posted 'I agree' comments, that's the point. Numbers show the viewers sentiment towards a comment without clogging the thread.
It is self-evidently true that removing visible comment scores mostly removes methods for trivially measuring "viewer sentiment". It is the contention of those in support of non-visible comment scores that trivial measurement of viewer sentiment harms, rather than aids, discussion. You have made no argument against that point.
EDIT: this -> parent comment