This one hits me closer to home, when my Grandparents were still alive they lived in Corning, Arkansas. Poplar Bluff was the closest city of ANY size to them(Corning had a population of under 5000 and I think I was related to a couple hundred of them - My Grandfather was one of eight and he and many of his siblings had similar family sizes. The youngest and last of his generation died earlier this week).
But I would imagine Medicare for All would be a godsend for rural hospitals - Medicare has much deeper pockets than just about any private citizen and doesn't try to find loopholes to avoid paying truly large bills like private insurers sometimes do.