Is there a specific line of the song that you mean or do you mean the “River to the sea” title/chrorus? Just checking if there is anything I might have missed.

But besides that, calling for the end of an state is a pretty normal anarchist thing to do and something I wish for all states in general and for states like Canada, USA, Israel and similar ones in particular because of the settler colonialism happening there. While it should be obvious I also want to clarify that calling for the destruction of a state is not the same as calling for the extermination the people it rules.