Lack of application of yourself is not an INTP trait. I'm full on INTP, and I can apply myself thoroughly when something challenges and interests me.
INTP is a large population with nuances, we're not all the same. But I think a general INTP trait that we all have in common is multiple interests, that are intellectual, and we tend not to enjoy ruts. I need change after a couple years.
I don't think that interview is enough to classify him, and I don't think it matters anyway, but I think I could see my life following a similar path as his. Not so much the exact details (though I am planning on medical school), but the path. Moving around, deciding I'd like to try something completely different because it looks fun/interesting (law enforcement seems fun).
I'm already a paramedic/firefighter, so I can vouch for the ability to apply yourself as an INTP. Paramedic school isn't med school by any means, but I did actually have to try (which I understand is the exception to the rule: INTPs don't really ever have to try to pass.)
