I'm actually withholding judgement on this. The fact that the WP pulled the original headline within an hour suggest to me 1) there is a real anti-Trump bias problem there, and 2) someone blew the whistle and the WP yanked it fast. The yanking of the headline is a tacit admission that they screwed up.
So if his campaign lifts the ban after a week or so, and that causes the WP to pay a little more attention so crappy headlines don't come out in the first place...I wouldn't really have a problem with that. I mean, as much as I think he's a gigantic douchenozzle, there is a giant feeding frenzy by the press trying to spin things, even when he's more or less right. They absolutely hate him. So...maybe this isn't such a bad move.
What kind of bugs me about this whole thing is that I think Trump's response was a hell of a lot better than Hillary's, and particularly Obama's, and yet the press is giving them a completely free pass. I don't think all of us should be aiding/abetting that just because we don't like Trump.