However, once the mob is engaged, it's unfair for someone that was (for example) afk or in a dungeon when the information came across their linkshell/FC to either 1) show up and reset the mob themselves (usually only happens if it's a small group fighting it with no tank) or 2) get someone in their linkshell/FC that's already at the fight to reset it so that they have time to get there. You were otherwise engaged so you lost out on this particular one.
I agree!

But that is just one of many possible things that could happen. Not all reasons for resetting are "right." Just like not all early pulls are "right."

The only thing clear is what's against the rules and what's not... but that's not the same as right and wrong.