I've never heard of a closed permit in the case of a Canadian citizen, though.
Presumably, closed permits for foreign workers give the employer much more power than any employer dealing with Canadian citizens, who don't have closed permits.
I was a freelancer, in my previous life. I had a contract job. If I wasn't happy with my contract, as a Canadian citizen, I could walk away. Right now, there are workers who don't dare report their employer. We're told that if they do, they're put on a blacklist of people not to be hired.
In my opinion, there's no right or wrong answer, but, logically, we can't keep this program as it is now. I don't like to see people saying, on the news, that there are cases of abuse in Quebec because of a federal program that obviously isn't up to the task.