The Canadian website says that their side is not impacted by shutdown, ofcourse, so they are asking people to come to interview as planned but will have to reschedule interview for US officers at a later time to complete the process. For some people it might give them an additional opportunity to visit Canada and for some it might be irritating lol.

Link:
https://www.cbsa-asfc.gc.ca/prog/nexus/menu-eng.html