I guess I disagree with you initial comment in that it’s saying to me that most Christians deliberately learn about Christianity with the express desire to ignore it. I don’t think that’s the problem “most” Christians would face.
I think a bigger problem is that many Christians invent this relative scale for the “badness” of sin. And so I agree with you when you say same you can’t campaign against strongly against same-sex marriage or abortion and be indifferent to people having sex before they are married, committing adultery or porn. A lot of Christians are like that because they imagine that one “sin” is not as bad a another. But a lot of others are quite genuine but have a thorn in their side that they genuinely wrestle with.