Fun fact: A good number of Greek islands end up using desalination.

E.g. https://www.nationalgeographic.com/science/article/partner-c....

And this is not by choice: Greece has to deal with extreme volatility in resource consumption throughout the year. Add to that it has ~6000 islands (around 200 being inhabited year round -- 227 as I google). And the tourist island/islet focus changes throughout the years. With this context, there can be no "I will create a pipeline of fresh water" or any other project like that really.