I think we had some "competents" in Congress back in the day, a few of them, enough to matter at times, folks like Sam Nunn who I liked quite a bit. Some others were willing to compromise, Tip O'Neill and Reagan for example.
My theory is both parties have learned they do better by keeping us polarized, and the presence of social media and the national "news" media contribute a lot to that. If "we" are convinced we must HATE DESPISE LOATHE the other Party, we donate/volunteer/vote for "our team", and we don't want ANY compromise that could help the other team. It's like OSU-UM in a sense, you WANT the other team to lose every game.
I see folks on FB constantly deriding the other side (and ignoring the problems with their side), same on any other social media I might see. I think "we" used to be 15% on each side die hard partisan, and now it's closer to 30% on each side. They'd poke a stick in their own eye if they thought it would harm the other Side.