Tell that to the organizations that rated him in the top three for most of the late 40s and early 50s. Ive never heard the argument that a fighter had to be unbeatable in his division to merit a title shot. If that were the case titles would be defended once a decade. Its debateable either way whether LaMotta was the best middleweight in the world at tue various times he was rated #1. How many fighters rated #1 can make that claim? Were Zale, Graziano, Cerdan, Turpin, Olson, etc a lock for best middleweight in the world when they got their title shots? Hardly. To argue that LaMotta hasnt earned his shot at the title is asinine. The guy fought tons of killers black and white often on their home turf or neutral territory, he was rated right at the top for years during and after the war and was artificially kept on the shelf by the mob and a champion who was just looking to cash out while kicking the can down the road. Claiming he only got his shot because he was popular and an earner is ridiculous. After the Fox fight he was a pariah and his earning power took a huge hit hence the Cerdan fight drawing less than hoped for by the fledgling IBC.
A fighter doesn't need to be unbeatable to get a title shot but back in those days you had plenty of talented guys who never got title shots. LaMotta never getting a title shot at all hardly would be unusual given all the guys who never received title shots. Lloyd Marshall never received a title shot and he beat LaMotta. Neither did Robert Villemain who also beat LaMotta. Or Dave Sands, etc LaMotta never getting a title shot would probably be an injustice on par roughly with Jack Chase not getting a title shot or George Benton not getting a title shot
Zale was well past his best but had looked good in the 3rd fight with Graziano just 3 months earlier, where Graziano was favourite to win. Cerdan was well past his best too though. Not quite as much as Zale but still a good few years past his prime.
Rocky drew $. That may have been an advantage. Though Lamotta had a good following in Detroit. Follow the $ to a certain extent. LaMotta was much more worthy than Rocky at any point. He was fighting very good and great fighters black or white.
Well, let’s see. Before his title shot (we won’t even count those he faced in title fights at Middleweight or any of his run at Lt. Heavy) LaMotta beat: Ray Robinson, Jose Basora, Robert Villemain, Bert Lytell, Fritzie Zivic, Tommy Yarosz, George Costner, Joey DeJohn, Holman Williams, Tony Janiro, Tommy Bell, Jimmy Edgar, Bob Satterfield, etc. Many of them multiple times. In his entire career George Benton beat: Joey Giardello, Freddie Little, Holly Mims, Lester Felton, Bobby Boyd, Jimmy Ellis, etc. Jack Chase beat: Archie Moore, Lloyd Marshall, Aaron Wade, Eddie Booker, Harry Mathews, Oakland Billy Smith, Big Boy Hogue, Leon Zorrita, etc. If you meant both of them combined, then you have an argument. Feel free to take out names of those who were past prime or smaller or what have you. There were several, but they didn’t just apply to LaMotta’s opponents, so subtract at the risk of your own argument.