“This technology does not exist “
And won’t until it’s developed. As for ugly, that depends on details yet to be discovered.
Perhaps not at sea- perhaps somewhere where there is both wind and water, especially water that is not useful for anything else, like sewage plant effluent ( a sewage plant tht makes methane too).
Low power density, intermittent sources are not suitable for main grid, but anywhere that the energy can be added in economically is a boost. Back in the 40’s pumped storage was not feasible, now there are places where they pump water to a tank on a hill and reverse the flow through a generator during peaks.
In that case why don't we use dilithium crystals like on Star Trek.
No need to build real power infrastructure, just wait for the dilithium crystals....they are right around the corner!!