Briefly, it's unfortunately true that the international convention agreement doesn't automatically give individuals who are victims access to rights: there is a long way to go, but it's a first very important message. This convention has been signed by no so-called developed country. So this would give Canada the leadership to send a message about the extent of migratory flows and the importance of regulating them.
Second, it would give us authority and legal power to say that we can and must reform federal and provincial statutes following signing and ratification by Canada. For the moment, we can't avail ourselves of that convention. So we can't approach the UN or Canada to change the laws.