This is one of those "hopeful upsides of driverless cars" that has been discussed. I'd like it to come true. Are there many mornings where I'd be perfectly happy to wait 5 mins for a my Waymo or what have you to swing by my house to pick me up, then maybe pick up a neighbor, and drop us all off downtown? Yep.
Also, just the better driving on freeways matters. Like this morning, when I got stuck behind a gal in a Kia Rio who would routinely drive slow as shit when the speed of traffic picked up, leaving 5-6 car lengths in front of her. That makes the traffic as if there were another 5-6 cars on the road. The optimal way to drive in traffic is to leave the minimal safe distance between you and the next car, and do NOT leave huge gaps. Driverless cars will do that well. So, maybe fewer cars on the road, and the ones that are on the road will drive better than many human drivers. Again, with tech that actually performs, this could be a very good thing. But....we'll see.