Raise your item level to 119 by completing a tutorial quest!

[Catmato]

Obviously those crabs would not aggro you if you were really level 119, a full 20 levels higher than 99, when those mobs were IEP and really were borderline aggro already. They are aggroing your 119 Jobmaster, because you are still level 99, and still just inside the aggro limit.

That's not really accurate. Everything that was aggressive to a level 75 player is also aggressive to a level 99 player.