People can definitely hold different views at different times in their lives. Usually what changes people is older and seeing different perspectives, so it follows that for everyone who goes though these changes, there are some (possibly many) individuals who played a part in "saving" them. So, it's always possible to be that kind of person for someone.
People get exposed to a lot of contradicting information in their lives, so it can be confusing to know what the right way to live is, particularly for young people. People being welcoming to former left-wingers actually trying to change their lives can make a lot of difference.
But yeah, the "saving" I guess only reaches people who are ready for it and want it, which is a tiny minority at any given time.