Simply being an insult artist doesn't make you politically incorrect.

Here is another analysis by Ace of Spades that I find to be right on:

Trump Opposes North Carolina's Different-Gender Bathroom Law: "Leave It The Way It Is"
—Ace

Prediction: within 24 hours he announces a major reversal on this plank and begins using the most extreme language possible to put him in sync with what he imagines conservative opinion to be.

"North Carolina did something that was very strong, and they are paying a big price and there’s a lot of problems," responded Trump.
"North Carolina, what they are going through with all of the business that’s leaving and the strife-- and that'a on both sides. Leave it the way it is. There have been very few complaints the way it is. People go, they use the bathroom that they feel is appropriate, there has been so little trouble," he said.

"Strong" is one of Trump's favorite words. He usually means it in a positive way when discussing his own policies, but he occasionally deploys it as a nice-sounding put-down to mean "too conservative."

Trump is a very reactive and improvisational guy. By which I mean a bullshit artist. He's trying to figure out what to say he believes at any given moment, rather than having a core of things he actually believes.

Although a good case could be made for the electoral viability of someone who wasn't so damned ideological about about everything (as Cruz is), we constantly see the limitations of Trump's no-core-beliefs belief system as well. Not having an intellectually defensible position (as he hasn't thought much about these things) and not having a core of things he feels strongly to be true (again, as he hasn't thought about these things), he tends to guess, get the answer wrong, then come back with a harsh formulation going the exact opposite direction to try to prove his non-existent bona fides.

Now the guy who's selling himself both as "Mr. Anti-Political Correctness" and as a guy who can reconform himself to be "presidential" and broadly acceptable to the public veers too far to the left side of that balance. When he gets pushback, which he will, he'll wind up veering too far to the other side; he might start talking about bathroom rapes. Which are a real thing, don't get me wrong. But such things have to be discussed delicately; you wouldn't want to make it sound like most transgenders (or most Mexican immigrants) are rapists.

Well, no use criticizing Trump for things he ain't even done yet. But I've seen this movie before. He doesn't really understand conservatives, and when his natural liberalism gets him into trouble with his conservative supporters, he drops something ugly to convince them all he's really "One of Them."

This episode does smoke out Trump as to which things he's "not politically correct" about. There is definitely a class of things he's not politically correct about -- sometimes about immigration, but mostly about affronts to Mr. Trump himself. When challenged, he behaves in a decidedly "politically incorrect" way, which most people would simply call "rude" and "ill-mannered" and "coarse."

But on the things conservatives really want him to be politically incorrect about -- challenging the tyranny of liberal assumptions which so easily dictate liberal conclusions (as they're designed to do) -- he's reliably politically correct himself. Planned Parenthood is an important, fantastic women's health resource. I'm softening, I'm changing my position on H1-Bs -- we need these great people doing the jobs American's won't do (or can't do). Forcing schools and businesses to allow men with penises in the women's rooms has caused so, so few problems, in all honesty, if I can be frank.

One might question: on exactly which questions, apart from immigration (partly walked back, and probably walked back even further in interviews with the New York Times) and defending himself personally, is Trump actually politically incorrect?

Simply being an insult artist doesn't make you politically incorrect.

Obama's an insult artist too.