The point being debated was whether it was God's perfect will for anyone to be sick. You said it was "ridulous" that God's perfect will was for us to be healthy. Do understand the difference between God's perfect will and what He allows yes? If not, I can see why you are stumbling over this one.
You said God wants everyone to be in perfect health, and that is not true, obviously.
If God wanted all men to be in perfect health, then all men would be in perfect health.
He's God. He gets what He wants. It goes with the job description.