1) Common context and language - there are 11 or so million users but we all knit or at least do some kind of yarn crafting.
2) Individual users and group administrators can selectively enable/disable these "click to comment generically" shorthands - so if a group moderator doesn't want Disagree whining in their group, they turn it off; if an individual user doesn't want to be bothered by seeing these, they can hide them.
Also, Ravelry has 6 of these for nuance:



