The reasons: Illustrative purposes. Yes you can promise to buy local/ only from Democratic States like Canada, or Australia, but purchasing fuel is left to the owner of the plant. If the owner decides Uranium from Russia, Kazakhstan or Uzbekistan (or via some other non santioned country) is better/ cheaper, there is little to nothing stopping them from doing so.

I'm aware Canada and Australia are among the top 10 producers/reserve-havers.

My point: it's a different matter for non Uranium- having Countries in the world. Same with Rare Earths and Battery tech or using Russian ahem Indian gas in Europe, but that is maybe a different conversation.