I've found that many people stop emotionally maturing at about 18-25 years old. I'd like to believe that there's some way to break these people out of this "rut" - possibly through class consciousness or some other thing that might open them up to more introspective thought patterns.
I was admittedly racist and Islamophobic and a bit of a bully as a teenager until I was about 19 or 20, having grown up in a very very rural American town where that was basically the norm. I found my way to where I am now via years of introspection, exposure to more diversity, and opening my mind to trying to understand things like class and anti-imperialism (probably initially by good faith exposure to Israeli apartheid and the Palestinian genocide). I'm definitely not a "finished product" by any means, but I'm a much better person than I was back then (over a decade ago now). This leads me to hold out some sliver of hope that there is some way to move the needle with the people who are like I was when I was younger.
At least for people with my background, I do think there are a surprising number of them that would be open to left wing beliefs if you could somehow break through the endless layers of right wing propaganda. If you talk to enough of them, they will occasionally say something that sounds like they're essentially paraphrasing Das Kapital, but somehow they come to the conclusion that the solution is hating immigrants and lowering taxes for the rich.
I've been back and forth on this for some time. My partner and I have discussed leaving, but we both seem to always waffle on it because we don't want to leave our family and friends.