The POTUS did not raid Medicare. The $716 billion are actually savings over the next 10 years that are not paid by the federal government to private plans that are well beyond the actual cost of providing benefits. The $716 billion was never raided nor cut, it was saved.
i.e. If a $20 shirt is on sale of 20% off, I pay $18 for the shirt. I save $2. The $2 stays in my wallet, it hasn't gone anywhere. I have not spent the money. The cost of the shirt has been cut by 20%, but not the quality of the shirt is the same. The seller takes the lost; not the buyer.