I suspect that "zoning out" will be a big question as these technologies are brought to market albeit in a different way than you describe. Many of the things being worked on will likely be useful and potentially available as assistive systems well before they could be delivered as part of a complete autonomous system. However, there will almost certainly come a point when you can provide too much of certain kinds of assistance unless you're prepared to actually turn over full control to the system.

You can't have a system that doesn't need a person to do anything 99% of the time but requires that same person to take over control at a moment's notice to deal with some situation that the computer doesn't know how to handle or, indeed, didn't even recognize.