The Interac debit system is Canadian. I would like to see it expanded to include a credit division that does credit cards like Visa/MasterCard, but since we are a much smaller market than the US, we wouldn't have nearly as big of a cushion if there were to be any sort of major fraud activity. But for me, local purchases are always debit. I only use my CC for purchases where my debit card isn't accepted (which is basically only online shopping).

GNU Taler is based in Europe, I believe. But seeing as it's free software there's no reason not to use it in Canada.

or maybe start accepting Euros to pay taxes

Why would Canada ever accept taxes in anything but Canadian Dollars? You get paid in CAD, and taxes are automatically deducted for most jobs. Exchanging to a different country's currency first makes no sense and would give control to EU institutions for no reason?

Canada has the resources to set up their own system. They could easily expand Interac, which covers a lot of types of transactions already, at least in-person. Online shopping is going to be an uphill battle getting all the merchants to accept more than just Visa/MasterCard, but maybe with Shopify being Canadian they could make it easy.

They should try the Brazilian PIX.

I've been saying this for a decade now.

Even more since the censorship on steam happened.

This can be really useful as long as alternatives are not made unavailable. Any digital payment processor/system can have some avenue for tracking, which can lead to sale and/or breach and subsequent exploitation of data. If one payment method becomes the only payment method, the privacy implications can be significant no matter if it's a private or public run method.