In the U.S. federal system, states often act as policy test sites. A state may try a new law. Other states may copy it. Sometimes Congress later turns a state model into federal law. Eg, unemployment insurance started as Wisconsin program.

The answer to your question I believe is that politics are no longer local. Instead politicians are punished if they don’t mimic the daily talking points from the national committee. That is politics is no longer about solving real problems but is about who swears unswerving loyalty to the party ideology.