The last amendment was passed 30 years ago, and the one before was 50 years ago. Maybe most of the politicians in charge only pay lip service to an issue, and don't have the will to die on a hill for anything, or leave anything for those who come after them.

I think it's a combination of it being too hard, and politicians "saving" issues, keeping them live, to motivate voters. Many times in the past 30 years the dems could have passed a federal law protecting abortion rights.