Theres a few differences in how the subject is used, when someone is "joking"about using them and its unclear whether they really are or not, the ones that troll saying they or a friend are cheating to get staff on them and those that accuse someone yet have no proof of the accusation whatsoever, these are some examples of the ones we dont want as it causes unneeded work on behalf of staff.
The hacksucating thing is frowned upon because calling someone out gives them a heads up and can make staff job harder as the player may now be more careful knowing they may be caught, thats why we tell you to instead contact a staff member and not just call it out in chat, joking about it where it is very obviously a joke is fine when it isnt out of hand some examples are when a player sees an admin flying and calls "hax" or when a group of players jokes about it with eachother be it due to someone being good at pvp parkour or etc.. (and again its very obviously them joking) in this example they arent calling on staff to get them or trying to convince others, theyre just kidding with eachother in a way thats not problematic, in a sense that is what the server response is, a joke that is obvious to all and has no need of being looked into and therefore not an issue.