3 franchises with no real history of success - it's not as if they were beacons in their respective leagues until new ownership tanked the brand/team. The Lions were only reasonably good for a small window because of one superlative player (success in the 40's doesn't count), the A's through very creative back office work and the Kings haven't been worth anything since Peja. Dallas, on the other hand (despite not winning a SB since I was a 13 year old child) is still second in the league in Super Bowl wins at 5 - like anything in life, your expectation sets your level of disappointment and is the barometer for the measure of success - and a guy in charge of the most valuable company in the world hasn't produced results for his shareholders (fans) for 3 decades, despite having the most recognizable brand in sport. He's an abject failure, frankly and the comparison to 3 shit box franchises is completely disingenuous.
The only team I can think of off the top of my head who "should be good" (based on revenue, success, fanbase, insert other relevant metric here) is probably the Knicks, who yeah, may be a worse run franchise than the Cowboys. God bless them. But at least they got Linsanity