There is a certain type of Republican who still carries a torch for Mitt Romney. To them, Romney embodies principle and integrity. But most Republicans still see the halting candidate who flailed fruitlessly at Obama, the professional careerist who has morphed more than once politically, and whose latest transformations are equally agile.
The Washington Post op-ed is everything conservatives despite about Romney in a nutshell.
There is the choice of venue. WaPo is a government insider paper, one that violently loathes Trump. Publishing an attack on Trump in the Post isn't a statement of principle, but an act of pandering to the political elites of the swamp.
And everyone knows it.
If Romney were trying to have this debate within Republican circles, he might have aimed for the National Review. Running an op-ed in the Washington Post isn't really about attacking Trump, it's about polishing his credentials in the mainstream media.
And that's exactly what conservatives loathed about Romney. They always sensed that his first audience wasn't the town hall meeting, it was the media. That he was so bad at it, only made it worse.
And the media is still Romney's first audience. Having gotten past an election, all he can think of is trying to win over the media. And he's always willing to sell out conservatives to make it happen.