I think smart monitoring will be a big help for a lot of people. When my Dad's dementia was getting worse, he liked to get out of the apartment and wander. My Mom had a hard time keeping an eye on him 24 hours a day - keep in mind that she needs to sleep, shower, go to the bathroom, etc., and Dad seemed to have a knack of talking his 'walks' during those moments.
At that time he really wasn't so bad off that he needed to be in a full care facility, but he was definitely not well enough to be wandering outside. Actually, even when it became time to find him a full care facility, it was nearly impossible because he was deaf and mute and nearly everyone said that they were not equipped to deal with that (we fortunately did eventually find a place with a great staff run by a fantastic woman).
Anyway, at the time we looked for some sort of monitor system that would help and were unable to find a system that would meet our needs. I'm sure things have progressed quite a bit since then; these systems will definitely be a big help.