If democracy isn’t working and you’re looking for an outside authority to start forcing your agenda on people, then what you’re looking for is tyranny.
The ECHR rules that Switzerland has failed to meet its treaty obligations WRT climate action. IE, there's been an internal failure by Switzerland's government and courts to enforce its own legislation and treaty obligations. So, these women took the next step - an international court (to which Switzerland is a party - if the Swiss don't like it, they should vote to abandon their obligation to the ECHR).