I'm not exactly sure I understand your question. I think what you're referring to is the capacity of provinces to borrow at reasonable rates because of the fact that their fiscal situation is sounder than it would have been.
The bond rates applied to provinces is usually that of the federal government plus a premium that varies across jurisdictions depending on the perceived risk of each jurisdiction. It's true that the fact they did not bear the brunt of the pandemic response or the cost of the pandemic leaves them in a better fiscal position. Without that, their debt levels would have been higher and the premium they have to pay compared to the federal bonds would probably be slightly higher than it is.
The counterfactual we will never know for sure because there's no way to run that experiment, thankfully.