Balancing power over ever larger areas does run into problems with long distance inter-connectors and spare capacity in general though, so it's not like this is

Balancing power over ever larger areas does run into problems with long distance inter-connectors and spare capacity in general though, so it's not like this is an easily solved problem. The UK is well connected to mainland Europe with many large interconnectors and has an enormous abundance of off shore wind power because it's an island, yet it still nearly had brown/blackouts due to low wind coinciding with normal maintenance. That suggests the UK is hitting the limits of what can be done with wind power despite having a lot of it. Even if interconnectors were upgraded, that doesn't help if other countries are already using all their wind power locally.