Realistically you can only deprogram the ones that are open to it. And the best way to do that honestly is by listening and treating them like adults. Holding back on ridicule Etc. Asking questions about their beliefs that they themselves have never asked. That if they honestly look into what expose the Sham they’ve allowed themselves to be victims of.

They’re convinced that there’s an immigrant crime wave. There isn’t we know there isn’t there’s no data to support that claim. But don’t just shout that at them and dismiss them out of hand. Ask them to go Source information on that. Not from drudge Breitbart or Fox news. From an actual law enforcement source that is required to be truthful and accurate. Similarly they are convinced that all government waste and fraud occurs with entitlements. Which again is often the furthest thing from the truth. Again we have plenty of information and numbers to show that most waste happens in defense spending Etc. That generally entitlements while not perfect are some of the lowest fraud. Because of all the bullshit Hoops that have been put in place to hurt minorities and vulnerable people. Again don’t dismiss it outright or shout them down. Ask them to cite numbers from the organization’s involved to confirm their beliefs.

If they are honest, sincere, they will struggle and flounder. Even then don’t admonish or shout them down for being wrong. Follow up with more questions such as if you can’t find evidence of your beliefs. Maybe someone’s been lying to you and what you’ve been told isn’t true. Even if you do not leave there with them converted. You’ve planted the seed that might break them free. That’s about the only deprogramming the average person will be able to do.