Like I said before, this is a shift of historic proportions. I doubt Brad and Rick were predicting almost 260 House seats and over 55 Senate seats a week ago. This tsunami is on the extreme high side (or past) every forecast.
Some core theses of politics failed. There's clips of groypers and proponents like Steve Bannon in disbelief. Their entire thesis has been that if they ramp up the cruelty and culture wars, young white males would deliver power. That failed spectacularly. And now they have no idea what to do. They lost (or came close to losing) nearly every demographic. Young, old, white, non-white, urban, suburban, rural (in some places). Indeed, the biggest Democratic over performance was in Ruby Red states and districts. This is a 100 year flood. And some chuds are pretending it's just a bad leak.
And while I don't think Democrats have won any of these voters permanently by any stretch, no political operative can now take any vote for granted. People who have broken the taboo of voting for the other side may do it again. And that's what all these Republican politicians and strategists are worried about. People who have not had to campaign in Texas and Kansas in decades will now have to do so. This is the equivalent of California and New York becoming competitive for Republicans. Democrats would absolutely be in disarray if that happened.