A speech or a commercial is not a record of evidence. He’s a politician. Obama said he’d close quantanamo bay, end the Mid East war, and tie the minimum wage to inflation. Campaign promises are not a predictor.
They are evidence of intent. Success is a different question entirely, which is largely predicated on Congress. Remember, only Congress can introduce legislation. Sanders ran on the back of Medicare for All, but the odds of that actually getting passed even if he became president would have been very low. I don't know if Biden will be successful in his goals regarding criminal justice, as I don't know what Congress will look like next year, but a crime bill from the 80s does virtually nothing to predict what his stance will be when he becomes president. Any politician who has been on the job for more than a few years will have seen their positions shift over time. That is simply how both humans and politics work.