It's not clear if the items that are usable to test the Scrapper required Expulsom
to create, but if you can Scrap any crafted item and any player can scrap any crafted item you can scale up the current silk/leather shuffle and supply any of your characters with Expulsom
for crafting purposes.
This will take professions in a significantly different direction compared to early Legion since you won't have to pair an Expulsom hungry profession with an Expulsom generating profession like Skinning/Enchanting with Jewelcrafting etc, and you won't be gated on how many bloods you can acquire.
I don't have any Alpha access myself yet to test this further but I'm personally excited to see what kind of scale people will be able to take crafting in BfA if what I'm thinking makes it to Live, it's going to be somewhere between Obliterum on steroids and Primal Spirit trading in Draenor.