The UK already has internet censorship. The ISPs flatly refused to cooperate, but it is being done by the obtaining of court orders requiring the blocking of certain sites by ISPs, leaving them no choice but to comply. There is now a streamlined system whereby further sites can be added to the block list without the need for a separate hearing and order. CURRENTLY, this is being applied to sites believed to be assisting copyright infringement, but the same system could, in theory, be used to block other types of site.
Does it work? NO
It's an exercise in being seen to do something, but sites like Pirate Bay can still be reached from the UK, although it's no longer as easy as clicking a link to the from Google, which is effectively blocked. There is a separate system that blocks a secret list of sites that offer extreme pornography among other things.
It's likely that the system in Quebec, if implemented, isn't going to stop residents playing offshore any more than the US safe ports act has stopped US players. What will stop such players playing is the casinos themselves deciding to pull out of that market, which is why US residents have been without providers like Microgaming for a few years, but can still play RTG and much of the "dross" that the rogues offer from places like Costa Rica.
Far from protecting US players, the rules have driven them into the arms of the rogue operators as almost all of the decent operators have pulled out of the US.