So it does not make much sense to purchase an Ontario license to cover your butt if you unintentionally happen to drift on the Canadian side.
If you have no desire to fish the ca side there’s no reason to get it. I had one close call where I was fishing the ca side intentionally and the Canadian wardens pulled up, but I got across the river before they could get to me. It’s pretty easy to stay on the mn side.
To be clear, you can legally navigate across the line but you cannot anchor or fish.