It was actually the conservatives who were against Trump during the primaries. The conservative faction is the only faction within the GOP that Trump didn't gain a plurality in. He lost conservatives to Cruz. It was also the conservatives who formed the anti-Trump or never-Trump coalition which went no-where. Trump never received a Majority of any Republican faction, by that I mean 50% plus one vote. Besides, it is the traditional conservatives within the GOP that have become the new RINO's
Conservatives Are The New RINOs
All during the primaries and the general election, quite a few of Trump supporters wouldn't label him a conservative. They labeled him a populist, a nationalist, even a nativist. But few called him a conservative. Sure Republican conservatives voted for Trump in the general. They would have voted for any Republican, living or dead against Hillary Clinton. But let's look at how conservatives voted in this election and in past elections.
Trump won the conservative vote 81-16 over Hillary Clinton with 3% voting for Johnson
Romney won the conservative vote 82-17 over Obama
McCain 78-20 over Obama
Bush 84-16 over Kerry
Bush 82-17 over Gore
Dole 72-20 over Clinton with 8% voting for Perot
Bush the elder 64-18 over Clinton with 18% voting for Perot
Bush the elder 81-19 over Dukakis
Reagan 82-18 over Mondale
Reagan 73-23 over Carter with 4% voting for Anderson
Ford 70-30 over Carter
That's as far back as Roper research takes it. Trump did about average in recent elections. G.W. Bush bested Trump twice and Romney narrowly did. I think you're misreading conservatives within the GOP. I seen the term Alt-Right used on this site, I never have been sure what exactly alt-right is outside they supported Trump. Perhaps that is the better term to use for Trump supporters than the traditional Republican conservative.
One last point, exit polls show that 50% of the votes Trump received were anti-Clinton voters. Any Tom, Dick or Harry on the Republican side would have received their votes. Romney, McCain, either Bush, perhaps even Pataki as long as the last name wasn't Clinton. Only 41% of all Trump voters strongly supported Trump. I would say the Democrats definitely choose the wrong candidate.