klunderbunker
Welcome to My (And Not Sly's) House
Maybe... at first. but the problem with that detailed of a backstory if they are easily painted into a corner. These backstories aren't based off the truth so with the internet, people are going to know the truth. It's harder to change a failed gimmick and make it believable when you have this detailed backstory about who they are and where they come from.
As you mentioned in WWE Edge and Christian stopped being brothers. This is because, Edge and Christian aren't brothers. Most people knew this so they stopped acting like they were to see more realistic. that was simply a way to add a bit more realism to the product.
It's also a way to make the company look fake, which has rarely worked for wrestling, even though they seem to think it does. Also, I doubt most fans care about what the real story is or if it's realistic or not. Again, I'd point you to Undertaker and Kane, where people like having fun instead of it being all serious and realistic.