Tying anti-abortion positions so tightly to Christianity (especially, popularizing it among protestant sects) and elevating that to a concern above most or all others (American conservative catholicism) was a deliberate move by propagandists in the last century, not something that somehow arose naturally.

Ditto trans stuff becoming a huge concern all the sudden. That wasn't "organic", it's a moral panic ginned up by people with microphones.

There's at least as much cynical-politics-affecting-religion as the reverse in the topics and positions you raise.

[EDIT] My point, as it occurs to me it may not be clear, is that "well most are christian so of course pro-choice or other 'liberal' positions struggle" is not a great explanation of what's going on, because that association isn't so guaranteed as this suggests. Things like social and economic justice are heavily connected to and promoted by christianity in some countries outside the US, but much less-so here. Historically, they have been here, too! More-Christian or less-Christian isn't the only axis here, what "Christian" tends to mean as it relates to politics hasn't been static, and that change has been in no small part driven by elite opinion and propaganda for the purposes of capturing religion for political ends, not from grass-roots demand.