The FTX restructuring officer wrote a letter to the criminal court specifically arguing that SBF's argument was bullshit for all sorts of reasons, and the court agreed: "A thief who takes his loot to Las Vegas and successfully bets the stolen money is not entitled to a discount on his sentence."
Plus that argument and a few other statements he made showed his lack of remorse, which denied him credit under the guidelines for acceptance of responsibility, and probably factored into his fairly harsh 25 year sentence.