There is actually a very basic reason for this. Liberals tend to be less spiritual and less religious. When you don't believe in the existance of a higher power, you are being run by your ego.
What is the purpose of your ego? To keep you safe, to keep you alive. Very useful when in constant danger.
Once you get someone to believe something who is a slave to their ego, they are less likely to change their mind. Why? Because the ego will fight to retain the old identity. Once you admit you are wrong and change your mind, it's like the old you has died. That is what the ego is trying to prevent, because it has trouble recognizing the difference between the two types of death.
This is also why liberal professors and "elitests" are such smug . It's why liberals are so mean. When their ego is threatened, they do not have a spiritual source to turn to for guidance. It's their ego lashing out to protect themselves.
Obviously there is nuance and not every situation is the same, but overall this is why liberals were targeted to become allies of the deep state.