Most of these claims you make are simply untrue, or GREATLY exaggerated.
Partially true but remember: refugees were admitted on the basis of fearing for their lives in their home countries. So yeah, the law (and UN refugee conventions) do specify that one possible repercussion of returning to the protection of that country is basically admitting you are not a refugee. But yes, it's true that in being provided refugee status, you have less ability to travel.
I think the definition of "availing yourself of your country's protection" is quite unfair in that it includes simply using the country's passport. As for refugees admitted on the basis of fearing for their lives in their home countries, well, it's not necessarily fearing death but also persecution. There are a number of reasons why a refugee would fear for their lives or safety if they were living in their home countries but still be able to reasonably visit temporarily, like being able to escape the notice of whoever is persecuting them during a short term visit versus being more easily spied on and found if they were still living there. Also, they could have fled a war that has since ended, but given the long processing times, this could be 10+ years later and they are well settled in Canada and would not be able to adapt to returning permanently to their home countries (think particularly of kids who came at a relatively young age)
False. There's no specific answer on how long they must remain in those provinces, but basically any PR who remains in the province they were nominated to for a year is perfectly fine. (Show me a case where that's not true, please - I'm not an expert but not aware of any). Certainly no reason theh would need to stay in that province until they get citizenship.
The problem is the lack of any kind of official guidance of how long they must remain in the province of nomination. But to go back to the wording in the official documents, when you accept a nomination, you are "indicating to both IRCC and that provincial or territorial jurisdiction that you are intending to reside in that province or territory and that you will comply with other related program requirements." "program requirements" being the intent to settle in the province. Intentions can and do change after one has moved and lived in the province for a while, but if questioned, the burden is on the PR to prove intent. And how long do the program requirements last? There is no mention of length of time, so it follows that these requirements apply as long as one is a PR.
I do know some people who moved from their province of nomination after 2+ years and were questioned in citizenship interviews for having moved. If questioned, one needs to have an excuse that IRCC considers valid, such as inability to find a job in-province despite a fair amount of effort. You can't just move because of personal preferences.
And yes, there are PNP folks who move before citizenship and don't get in trouble for it. That does not mean that it is okay to move, just as some refugees do manage to keep their PRs and get citizenship despite a visit or two back home. The government does not enforce the rules in every situation, and also whether an excuse for breaking the rules is valid can be a subjective matter. But if you want to be safe and not risk being one of those who do get in trouble, you need to follow the rules.
Outright bullshit. Couples divorce and leave each other all the time after arriving. The rare exceptions of problems are where there is evidence that the original application was marital fraud. There is absolutely no reason a PR in an abusive situation should remain there because of PR status. They can move to anywhere in Canada with zero implications for their status, and without their spouse.
Divorcing before citizenship would certainly raise questions, and whether reasons for divorcing are valid and what constitutes abuse can be subjective. Again, if questioned, the burden is on the PR to prove that no marriage fraud existed. And just because some people can divorce before citizenship and not face any negative consequences does not mean that doing so is not risky.
Nonsense. After becoming a PR, they can move to Quebec too if they wish.
FSW EE immigrants applied on the condition of intending to reside outside of Quebec, similar to PNP folks who applied on the condition of intending to reside in their province of nomination. Enforcement of the rule to reside outside of Quebec does seem to be enforced less often than the PNP requirements to stay in province, probably because it is less common for FSW folks to want to move to Quebec, and those who do, already have good French proficiency and integrate well enough not to draw attention. Still, the rules are the rules, and if you break them, you are taking risks, if not of rejection of citizenship application and/or revocation of PR status, then of at least more scrutiny and delays in your application.
An analogy is how most people who commit crimes or infractions do not get caught. Most people have driven above speed limits at times, but most of the time, they were not caught. Others have committed petty theft and not gotten caught. But just because most people don't get caught, or you haven't gotten caught yet, does not mean you aren't breaking rules or that you will never get caught.