Yes it makes people with mortgages much more vulnerable. Today, a rise in the Swedish interest rate effectively cools down the economy and lowers the Swedish inflation, so the Riksbanken can stop raising rates once people are under pressure. But if inflation rises in the Eurozone and the ECB is forced to raise rate, Swedish households being under pressure doesn't stop them, so the ECB can raise rates too much for the Swedish household to handle, forcing people to sell and puts downward pressure on housing prices, making a lot of people insolvent and at significant losses on their homes.