Technically you can get the WW axe sooner? I think the slower weapon speed and the extra stam makes WW a bit better for grinding while hamstring kiting / low level PvP, but overall the difference is pretty negligible. I'm not a warrior main tho.
You can even put Ravager in the same category, and honestly sometimes its really quick to grab...
https://classicdb.ch/?item=7717
Guess it depends on your goals? Speed leveling it would be best to avoid all of them, buy upgrades as you go. PvP realm you may have more trouble getting WW as its mostly open world focused. Just sorta depends.
Is bonebiter a straight upgrade?
Yeah, pretty much.
Is it even worth getting the ww axe on alliance?
In most cases, yes. Realistically you wont be able to get Bonebiter before level 37/38. So even if you dont rush to get WW axe immediately but complete the quest around level 32/33, thats still a solid 5+ levels you will use it. And it will be a huge upgrade for those levels.
I guess most people dont really care about Bonebiter due to it being such a small upgrade over WW axe. And everyone wants WW.