this! and the over exposure of wrestling in general. theres too much of it. you can pick and choose when you want to watch. if you made raw 3 hours and took away smackdown, raw ratings would go way up.The only external factor that ruined the product was the internet. Kayfabe died, Smackdown spoilers (yes the internet was around when SD debuted but it's more common now), leaks promoted crazy last minute changes, downloads killed ratings, etc.
The rest of the problems are all internal issues.