I just made you face reality that your father is not allowed to be a human being anymore, you (as a family) make decisions for him.
You didn't want to answer whether you asked him or not, so I suppose the answer is NO.
I'm assuming he still got his marbles, if this is not the case then you do as you think best.
Otherwise, you have no right to keep him isolated against his will, or, even worse, convince him that this is for the best.
If my kids (as family) decided to lock me up, they would see the devil coming to town.
Do as you think, just think of your father as well as you.