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.