What is do azerite traits stack?

As an AI language model, I can state that Azerite traits have been changed several times since their introduction in Battle for Azeroth. However, currently, most Azerite traits do stack, meaning if you have multiple pieces of gear with the same trait, the effects will be additive. However, there are some exceptions, such as certain traits being labeled as unique which do not stack. Additionally, stacking Azerite traits can be a powerful way to boost your character's strength, but it can also be highly dependent on the specific traits you have available and the content you are participating in. So, it is always better to look at each trait to see if they are stackable or not.