Plenty of group chats that mix iMessage and sms, just through iMessage, or just sms group chats.

Most new Canadians I interact with have WhatsApp, however, as I understand that’s quite popular abroad.

I don’t know anyone in Canada that isn’t a new Canadian that uses anything other than the default sms app on their phone. (FBM and Insta and what not don’t count in my example).

SMS is alive and well in Canada.

Carrier pigeons. I haven’t gotten a response back in ages though.