I don't know where to start with your question other than to encourage you to watch all 2 dozen debates and what seemed like hundreds of Trump rallies from the recent primary and general election season.
I'd also reference the poll numbers of the campaign's most long lived centrist candidate, Gov John Kasich. Somewhere around 5%, I think.
I reply saying that your response is an apples and oranges comparison!
We are focused on House members, the Representatives that were elected or re-elected by voters (mostly GOP voters, but not exclusively in many cases), in contrast to General Election Trump voters.
And let me be very clear, in my personal opinion, Trump screwed up royally on the campaign trail with respect to his rhetoric on the fate of the ACA.
To be succinct and not have to dig up a volume of direct quotes, he spoke out of both sides of his mouth on the subject. On one hand he would often say: "Day one folks.... day one.... what are we going to do? That's right, get rid of Obamacare..... all of it, folks.... all of it..... its got to go folks.... its got to go..... it is hurting too many people... its bad.... Day one.... Day one we end it..." (or something very close).
On the other hand he would say: "Folks we are going to replace it with some better.... much, much better.... we are going to have fantastic choices for everyone.... that's right.... everyone.... a lot of Republicans won't like my plan.... they won't.... but we are going to cover everyone..... even those that can't afford it.... we've got to folks.... its the right thing to do.... its the right thing to do...."
I suggest that in light of the above, there was a LOT of selective listening going on.... many people heard what they wanted to hear from the above.... and either ignored (or rationalized away) what they didn't want to hear....