I am a supporter of Open Media but not on this one.

• Changing the law in Canada will not change it in other countries and your phone and laptop will still get searched by border agents of other countries where you basically have no civil rights anyway.
• Border agents in other countries can and will report anything they find to the Canadian authorities, so even if Canadian authorities do not look inside your phone, if you have something illegal they will be told anyway by the other country's agents and you will get charged anyway.
• International agreements on certain types of criminality, like drug trafficking, human trafficking, war crimes and sex tourism (with underage people), allow Canada to prosecute the accused in Canada even if the crime is committed abroad. So if another country finds evidence linking you to these types of crimes, you can get charged in that foreign country as well as in Canada.
• If border agents are barred from looking into phones, laptops this will not apply only to Canadians, it will apply to anyone crossing the border, tourists, immigrants, refugees but also drug dealers, human traffickers, child pornographers and potential terrorists.

I read a lot of comments on r/Canada about people who DEMAND refugees and other foreigners to be vetted more carefully at the border.

Lots of people who support refugees and immigration also want to weed out criminals at the border as to ensure the good people are getting the help they need.

Few people, when asked, would agree to let someone with a criminal past into the country, even the biggest bleeding hearts put a stop at child porn and human trafficking.