The reason it's ranger only is because it has a light heal skill on it, rangers warriors and rogues can use spears, but only rangers can use light heal, so therefore it seems logical that it's a ranger item if it gives a skill boost that only rangers have. If it was a different skill lets say 'sneak attack' then it would have been a rogue item etc..
That's fine, though the reason it has spear skill is still unanswered.
Look I know it's not gonna be changed , I don't expect it anymore.
Please recognize how hard it is to kill Aggy , how hard it is to then get a drop . I think my clan has killed Aggy 22 times now, we have 2 ranger and 1 rogue bracelets to show for it. Mages and Druids have more skills so the random loot generater makes more Mage and Druid loot for Aggy , at least make sure the loot made for ranger and rogue is good.