"Immediately" can mean a bunch of different things in a driving context! Here it means "within ten seconds". Which is both short and long: it's long enough that many of the things you might want to do that take your attention are fine (reading, watching a movie, working) but not long enough that you can sleep.

> This is about the peak of what you can get with automated lane keeping and braking.

Are you saying that within 5y, say, we won't see a level three system that's able to handle full highway speeds?