Second point: you're entirely wrong about voting patters being elastic enough to overcome gerrymandering.

1. Hyper polarization means that even HORRIBLE candidates like Donald Trump or Roy Moore only earn a few percentage points less than the generic Republican in the general election (there was only a ~2 point gap in the general election in 2020). So, no, even nightmares of human beings won't change a R+15 district into a Democratic one.

2. What we learned from polling on Gay marriage was that only gay people and religious fundamentalists cared deeply about the issue. Fundamentalists vastly outnumber the LGBT community. Getting the general public really angry about gay marriage going away simply won't happen, because it doesn't affect the vast majority of them. Gay marriage was always a much more important issue to the GOP base than the Democratic base.

Between hyper-polarization and the fact that only the fundies really care about LGBT issues, whatever happens to us won't swing the outcome enough to make a significant difference.