Writing as a fan of the americano, I think we should just call it what it is. After all, what’s more american than taking something good and watering it down?
Alternatively we could call it the italiano since that’s where it originated. Or “café à l’eau” perhaps, what’s more Canadian than randomly adding french. Calling it “canadiano” feels too “freedom fries” to me.
It’s not the same situation as freedom fries at all, but it has the same sort of cringe feel to me. Just like french fries, the americano isn’t really american. We’re not ‘sticking it’ to anyone here, so it rubs me the wrong way a little. I hardly have a strong opinion on it though.