If you're going to piss people off by removing the headphone jack, you don't do it again by changing ports next year. You tear the bandage off in one go.

Yes, I mean it exactly like that. Apple could and would switch if it provided them significant benefit (smaller, more robust connector, ability to make the phone thinner, new capabilities). I don't see that USB-C provides them with anything except a loss of control over the connector and a bunch of annoyed customers.