What makes you think that that sentiment itself isn't fostered by controlled opposition? Don't get me wrong, as an anarchist I have no love for Democrats or republicans. But unfortunately with our electoral system the way it is. Realistically we have to be bedfellows with one or the other at some level of government.
At least of course until all national parties are abolished, and the electoral system reformed. Trying to push change from the top down has backfired every single time. The unions thought it would be good to give Carter a lesson. And instead Carter lost and they ended up becoming irrelevant. There's plenty of parallels between that and the recent presidential election. Honestly I don't think the Office of the President shouldn't even exist. It's too much power just begging to be abused as it currently is.
That will only change however by building up local parties and making National parties irrelevant, or at least serving the interest of the accountable local parties. Till then we can gnash and wail, grinding our teeth at every shitty candidate the National Party puts forward. But as long as they are in control and full of shitty candidate fodder. That's never going to change. But us focusing on that over everything else certainly enables the worst actors in society.