Cody was great as a midcard act with the "Dashing" gimmick and in the tag division with his brother, but he's not a main eventer at all. The indy scene is giving him the TNA-hiring-any-WWE-talent treatment and it's super corny and forced.
It's not your place to determine where Cody should be on the card, nor how he should feel about it. It's up to WWE, then up to him to agree or disagree. He disagreed, so he left, and he's doing very well for himself.
Dudes have been shytted on on here for staying in WWE to be jobbers. Cody didn't want that, and I'm not mad at him for it.