If anything, random contact with other (non-work) people when you have a family is more important. Otherwise, your world will become very closed. They say that marriages with affairs actually last longer 🙂
I like the French and Italian philosophy that doesn’t require married couples to spend every waking hour either alone, at work, or with each other.
As far as self-driving cars, the problem is reasonably simple on a freeway in clear conditions. The problem becomes a good deal less simple in any sort of semi-urban environment with pedestrians, cyclists, etc. A lot of negotiation of right of way is done via eye contact, gestures, etc, and having a self-driving car that will play nice with other traffic isn’t trivial.