The newsprint on that story was barely dry before Redstone's competency was again brought into question by the CEO of one of his companies who had supported Redstone in the previous case. The details of the Redstone situation are lurid and have major implications for businesses.
More importantly, however, is that these situations are becoming more common in the U.S. as the New York Times points out in "In Sumner Redstone Affair, His Decline Upends Estate Planning."
The problem is that as people are living longer and often with a diminished capacity, there are more opportunities for other people and charities to take advantage of them. Estate planning attorneys fear that their wealthy, elderly clients are being manipulated into changing their estate plans to benefit the person doing the manipulating.
Often this takes the form of a much younger woman manipulating a wealthy elderly man. It can also be that a charity manipulates a wealthy person into giving multiple gifts.
Unfortunately, even the best estate plans on paper cannot always prevent these problems from occurring. As long as people can change the terms of their estate plans there remains the possibility that they can do so after being manipulated. For that reason it is important that friends and family members remain involved in elderly people's lives to protect them against this type of abuse.
Reference: New York Times (June 2, 2016) "In Sumner Redstone Affair, His Decline Upends Estate Planning."