I think the issue is that they need to get the cost of generated...

I think the issue is that they need to get the cost of generated power down to a competitive level (with both fossil fuels and other renewables). Hence the recent move to islands, where the cost of power is typically much higher than continental (e.g. diesel generators). One can assume that Ceto 5 was not really cost competitive (since they refused to publish any actual figures of power generated while the buoys were deployed in the Garden Island trial).