The thing is, people are going to be harmed by Trump and his actions regardless. So the question becomes, what will cause the least amount of harm:
- Repeal of Obamacare, which harms millions of people who need health care, but turns enough of the electorate against the republicans in 2020 that the Democrats retake the white house and/or senate. After that, the Democrats can start repairing some of the damage caused by Trump and the republicans
- Republicans somehow keep Obamacare (or at least parts of it), enough people think "my health care is safe, no need to turn against the GOP", and either Trump or the senate republicans manage to eek out another victory in 2020, with the result of another 4 years of Trump (along with all the damage that brings) or another 4 years of a republican Senate