Romney isn't a politician anymore. That's why I think this carries more weight. He can say what he wants and doesn't have to worry about job security of appealing to the base.
Also, read the article. This is about the Republican primary. He can vote for folks near term still R. But he alluded to that in a general if it's trump, he'd probably vote Biden.
But "the others that are running are acceptable to me and I'd be happy to vote for them," Romney told "Person to Person's" Norah O'Donnell when asked which candidates he "liked" in the GOP field.
I get what you're saying, but that difference can also come from the fact that there hasn't been a single primary yet, let alone a Republican nominee. We can speculate on what that will look like, but speculation is not enough to turn that "would" into a "will"