Even though Volvo will be liable, however that doesn't really excuse them for taking the steering wheel away from the driver.
There is legal liability. However that isn't much condolence if you are in the car about to get into an accident which you could avoid if you could.
Except you can't, because you stopped really paying attention to the traffick the second the car began driving itself. You won't even notice you're about to get to an accident, much less have any idea what to do about it. At best you might get startlet and do something stupid, like unexpectedly slam the brakes in the middle of a highway. It's best to take direct control away from you except through some ritual which is complicated enough to ensure you're actually paying attention and have had time to think what you're doing. And yes, that will sometimes lead to accidents, but probably less often than the other way.
Besides, isn't getting rid of that whole "paying attention to the traffick and planning what to do" thing the whole point of self-driving cars? It's not like working the controls is physically tiring.