He didn't take "full responsibility" as that would have entailed several things including resignation from office, in my opinion.
What would I have expected: at an absolute MINIMUM, stop drinking, publicly declare so, and do it in honor of Ms. Kopechne and what caused her death in the first place.
As for the "joking" bit, there was a radio audio stream from a speech or gathering he was at. I wish I had gotten down the specifics and time, but I was driving to lunch and all. It was more like a comment in bad taste than anything truly horrible, but it summed up for me that he hadn't really come to terms with it.
