In France striking is a fundamental right just like marching (assuming you make the demand to the authorities and it gets accepted). However what I dislike about the situation is that everybody strikes and manifests for his own core interest separately. I think we should really get into a more coordinated effort. Most of those strikes have failed.
You're not asking for the authority to accept you to march, you simply announce that you'll march, which, as a fundamental right, can't be rejected by the authorities beforehand unless there are serious reasons to believe that major trouble will occur. Though in the recent years several protests were forbidden by the authorities, it still is completely exceptional, and the marches happened anyway (and of course, major fights with the police ensued).
I agree with what you and your brother comment say, however you are both missing my 2 main points :) Which are that being a fundamental right it is easier to do and also the right is misused in my opinion, we should consolidate forces instead of striking in turn each year.
This is not entirely wrong, but is misleading. Yes, striking is supposed to be a protected worker right, but there are entire regulations to follow for that ("préavis" / "droit de retrait" etc). However, it was not always the case and for most of french history striking was illegal and heavily repressed. It's important to note, because in the past decade or so there's been massive retaliation against some organized workers in certain corporations and even in public services like La Poste. Striking is only protected as long as the balance of power shifts in our direction, and it's fair to say that the bourgeoisie has been gaining momentum while we have lost significant rights since Sarkozy, and our protests have been heavily repressed including maiming and murders by cops.
As for demonstrations, what you said is incorrect. There is no obligation for the prefecture to approve your request before you go on a demo. There is indeed an obligation to declare it but unless it's explicitly forbidden you are go. It used to be, not so long ago that undeclared demos were legal and i believe it was only under nazi occupation that they weren't. Sarkozy changed that to repress young people hanging out in public spaces by making 3 people or more hanging out together illegal.
It's important to understand that outlawing demonstrations in France (along with other obvious signs of growing fascism) are a rather recent phenomenon. Except for workers/ecologist or pro-Gaza demonstrations repressed in the past decade, the last forbidden demonstrations in France date from the 60s (in support of Algerian independence).
