The folks who oppose ACA for ideological reasons and who have done so since the beginning -- some of them since 1948 in fact -- have a reasonable set of arguments on their side. Alas for them, they are a small minority of voters, although backed by some powerful special interests.
Research (not just polls) has shown for some time that what the majority of Americans really want is a single-payer, Medicare-for-all type entitlement although they are not clear on all the details since no such proposal has been on the table.
The current situation is one in which ACA is actually the least the electorate will accept, as Republicans surprised by the flare-up of support for Obamacare have been dismayed to discover.
Like Social Security and Medicare, some sort of ACA-like entitlement encompassing Medicaid is here to stay. Trump hasn't bothered to learn the details of these complex programs but months ago during the campaign he realized that getting on the wrong side of these huge entitlements is political suicide at the national level.
Trump is neither stupid nor a genius in this perception. The Conservative Party in Britain and sister parties throughout the advanced democracies came to this conclusion years, even decades ago. We were the last nation to adopt a national medical insurance system but the political dynamic in the USA is basically the same as it is in the rest of the developed world. Republicans who cannot accept this bitter reality are in for a drubbing.