Not all versions of Christianity are Sin-oriented, but those that are seem to get more traction in this era. There've been times when Unitarianism and Universalism (they used to be separate religion) and the Society of Friends (also known as Quakers)-- much more gentle religions-- were spreading, but they never got huge.

I suggest that people are attracted to drama at least as much as they are to things which are likely to make their lives better.

There may be an underlying premise that "anything which attracts my attention must be worth paying attention to".