If that’s his attitude, then he’s telling us that he would have been a bad POTUS. Not worse than Obama, but most likely very close to the same thing. Coveting the office is a bad sign. And what makes it worse, the obvious way to win—i.e. go conservative rather than liberal—was utterly eschewed by him and the GOP.
Coveting the office? No, I'd say it's more like regret in hindsight. Maybe he finally realizes how messed up things are with Obama and wishes he'd run a better campaign.
My hunch -- and it's only just a hunch -- is that the truth was somewhere between Romney lusting after the presidency and his son's notion that he really didn't want it and didn't care.
Is it possible that he really didn't know how bad things were before? It's possible. I suspect a lot of people were in the same boat.