"I'll add, part of the problem is the voters. They (we?)) have become more narrow and more politicized also. FB, et al, plays a big part as does the mainstream media with "10 second sound bites" (a long running problem)."
Is it the media affecting the public or the public losing patience and demanding simple solutions to complex problems? No one's got time to think the long game anymore; you snooze, you lose. Plus there's been a lot of backlash against "old boys' networks" as of late, which as some analysts have noted actually had a calming influence on politics but got swept away due to its main drawback of disenfranchisement.