"Should" can mean several different things in this context.

Is Canada capable of enforcing its legislation/regulation? Yes.

Does Canada have the moral right to legislate/regulate? Almost always yes. (I would say no if Canada just seized all of Facebook's property for no reason, but no one is proposing anything like that.)

Is it in practice a good idea for Canada to legislate/regulate? Maybe yes but maybe no, just like with any legislation/regulation.

Does it make sense for Canadians be surprised or offended if Facebook doesn't break the law but also doesn't cooperate with the intent of the legislation/regulation? Here's where I'm saying "no".

I don't consider myself evil, but If I were running Facebook, I would ask the experts working for me whether it was more profitable to pay Canadian news agencies or to stop letting Canadian people post links to news (keeping in mind that if Facebook pays Canadian news agencies, other countries will start demanding the same thing for their news agencies). The I would do whatever those experts said was going to be more profitable. My job wouldn't be to do what's best for Canada; it would be to do what's best for Facebook while complying with Canadian law. (In the same way that as a private citizen, I do what's best for me while complying with the law, not necessarily what's best for the government or for the nation.)