Politicians need both quantity of mild support and quality of intense support. The former provide votes, the latter provide money. But negative impressions of them do not matter in the same way. Dislike is only measured compared to other candidates. Thus it is important to keep generalised dislike at a mild level, so that your opponent(s) can be more easily portrayed as worse. But intense dislike doesn't matter much more than mild dislike. Those who hate you cannot take votes or campaign money away from you, they can only accomplish that indirectly by giving to your opponent - who they also may not much like.
This may seem obvious, but look at consequences. A thousand jobs on the Keystone XL pipleline were just lost. They have friends and family, certainly, but that is only a few thousand votes of people who are really angry at you. The mild positives you get from having done...something about the environment...y'know, a good thing like not having a big ugly pipeline...that might spill or something, which would be gross over a lot of ground...and those oil company people aren't trustworthy...
Or if you had a nice business in downtown Portland built over years, but now it's destroyed, and you are really angry at the lack of protection and you have politicians you hate that you used to like...well, what of it? Those are only a few votes. There may be some increased generalised bad feeling for some politicians, but even in Portland, even among your neighbors and (former?) friends, people are still mostly happy that "We still get to be Portland, y'know?" Their image of themselves can go on almost uninterrupted, and such bad feelings can be gradually redirected against other politicians and other groups. It's actually pretty simple, because people want to find ways to go back to hating who they used to hate and liking who they used to like. They will actually help you make excuses, as Screwtape explained to Wormwood about even Christians not wanting to face God sometimes, actively assisting their tempters in staying away from Him.
I don't think all this is widely understood. Conservatives think that "Whoo, boy, those people out of pipefitters jobs aren't going to like Biden much now, eh?" It's a few thousand votes max, and who knows if many of them were Biden voters anyway? That they mildly disliked him and were worried about him and now despise him doesn't much matter. It matters some. People talk, people become activated, their friends and neighbors do absorb some of this data that might connect to other negative things and change attitudes. But maybe not.
People who hated Trump also seem to have missed a lot of this understanding. They seemed to think that if the people who hated him could be convinced to hate him even more, then it would change the attitudes of the country. If anything, when hatred reaches a certain level it starts to send folks in the opposite direction. I don't say the intensity has zero effect, because it does enter the general atmosphere of the culture. Yet not so much as they imagine.
The weight, the quantity and quality, the intensity of like and dislike are not equal forces in politics.