There are many people who can’t let it be. They can’t accept the fact that others may disagree with them or make choices that they don’t think rational. And rather than let it be, they seek to force others to live by their choices and values.
To let it be means to accept the fact that individuals are not monolithic. We have a wide variety of values. Some people like the ballet, and some people like baseball. Some people are gay, and some people are heterosexual. Some people like parks, and some people like malls. Some people like chocolate, and some people like vanilla. So?
My love of chocolate does not threaten your love of vanilla. We each can pursue and enjoy what we value. I can, and do, let it be.
But if I seek to outlaw vanilla, I threaten your value. If I seek to outlaw the ballet, homosexuality, or malls, I threaten the values of many people. I no longer will let it be.
I do not mean to imply that all values are equal. They aren’t. But I don’t want others trying to impose their “superior” values on me. I want them to let it be. And I won’t try to impose my “superior” values on them. I will let it be.