So people who got Gold in draenor get the weapons across all toons, but MoP Gold armor sets are still character specific... why?
because they are super unique, and based on your class, and also with the weapons, anyone who dident do it on a warrior (to unlock literally every one of them) would feel ripped off... as some classes could only get 1 or 2, well warriors could get every single one of them...
also the mop armor is not character specific, its class specific, any warlock you make can use the warlock armor, any warrior you make can use the warrior armor, etc
also as said above were getting reskins, with slight downgrades, like chunks missing from it, paladins lose the shoulder wings, shamans lose the totems, warlocks horns are tiny
the only one that is just a recolour is the priest one, all the rest have changes in them to make them less special (also they dont have "on cast effects" like the mop ones, and in my opinion, most of them are weird colours, so only some people will like them)
It all has to do with class restrictions on gear and wardrobe.
Weapons don't have class restriction and adding something to keep CM weapons char specific would have been a lot more work, hence token to make everyone on par with warriors.
Armor sets have restrictions (class) and so you can equip them on new chars that are also that class. There is no class that has an advantage, hence no need for tokens.
And this also goes for pvp weapons/gear with rating requirements etc. If you had an elite set on some class, do you deserve to get all of them for all classes? You still can use the weapons because it would be too much trouble making restrictions with new system.