... and could be solved by a high-tech, or even a bunch of low-tech, devices. But electronic monitoring can only go so far.
If the elderly person cannot interpret what they are told by a screen (or a disembodied voice reading it), a human caregiver must be present. In a timely manner. _Every time_. A familiar son or daughter over the phone is not enough for someone with a form of dementia, or a case of Just Plain Stubborn. There is no substitute for being there.
As many commenters pointed out, eldercare will be monumental challenge for the next couple decades. Nursing homes, assisted living, and group homes will clearly evolve, as there will be more folks who need care, and fewer who can provide it.