Doctors here in Canada all have their own practices, their choice of how they deliver care, their choice of where they want to practice, how much time they want to put into it - why would a doctor lose his practice because of public medical care? We have shortages of doctors in some rural areas because most doctors prefer living in cities, but those shortages are usually short term: sometimes incentives are offered young doctors to practice in rural settings.

I live sixty five km from the city. There's a small 'emergency care' hospital about 20km away, attached to a nursing home. There's a medical clinic near that mini-hospital which has six doctors and three nurses in family practice, all with their own patients. One of them is my family doctor, but if I need an appointment before he can see me (he's very popular), one of the others will see me (I've never had to wait more than three days to see someone on a minor complaint - and that was my judgement; if I needed to be seen, I would get a same day app.). There are also plenty of single practice doctors in the city, and most specialists have private practices.

Doctors get paid per service, they aren't on salary.