And it remains illegal... but not for refugees which has be the case for over 60 years.

See S. 133 of the IRPA which currently implements our obligations in international conventions and agreements in respect of refugees dating back to 1951 to not prosecute a refugee for illegal entry or the use of false document to gain entry.

You are conflating immigrants with refugees.

Refugees are not selected on immigrant criteria but rather whether or not they are need of protection on the grounds set out in the international conventions and agreements that we have passed into our domestic law - the Immigration and Refugee Protection Act (note the duality of the name) and its predecessors since the end of WWII.