In my opinion, law is a bit irrelevant here. You should know what you want to do, if you don't want to do it then decline and see how it goes; If you feel like doing it accept it. Do not let those small details alter your aspirations, in the end all it matters is what you want to do. You are obviously skilled enough to find another job, so do not be afraid to stand up for yourself.
I think this is a bit of a narrow view. Even if I probably do what you say and decline it myself, personal circumstances will vary. I think law here is relevant since it is the minimum that the company will have to uphold and your case to decline will be stronger. You are right in that each person should think about what they want, but they should also balance it with their circumstances.
I'd say it's a perfectly reasonable request given that you manage over a third of the company. But I wouldn't be surprised if there was a law against it in Québec... worth finding out and informing the CEO if there is.
Is this a matter of principle for you or were you planning to go to some remote are with no Internet? If the latter, you could just explain the situation to your boss and they will probably understand.
Hi from another Canadian. Here in Ontario it is illegal to ask employees to perform any work-related tasks while on holiday and I am 99.9% sure the same is true in Quebec (we have an office in Montreal). Whether you wish to enforce that is up to you.
We actually ask people to unplug and recharge in my company - it makes for better outcomes long term.