As a Born Again Bible Believing Christian, I couldn't agree more - even amongst those who call themselves Christian, people don't listen very well, jumping to conclusions and responding wildly off topic.
Nevertheless, I learned on FB (which I quit for those reasons), people have different understandings of the exact same words. Beyond that, facial expressions, verbal tone and inflexion, and immediate corrections are completely impossible to achieve or absent altogether. Whether it's my writing skill or readers' listening skills which are to blame doesn't really matter.
Online conversations are difficult.