You've lost the thread.

Here's your original claim: "no guild ever let a vendor pick and choose what their capabilities were"

A carpenter's guild can prevent other people from doing carpentry. That is not what's being discussed here.

A carpenter's guild cannot force a horseshoe maker to begin making hammers. That is what's being discussed.

Your initial claim was analogous to "never before has a horseshoe maker been able to decline making hammers when the carpenter's guild needed hammers"

Obviously they have and any other state of affairs would be flatly insane.