Why put them in the ocean when you can just put them on the coast and pipe ocean water through the heat exchanger? That way you can actually access the servers without a ship with a giant crane (powered by fossil fuels) hauling them back up.

Also gonna guess the maintenance intervals are atrocious with all the salt corrosion. Why not a river or lake where the water doesn't actively hate the thought of metals existing and you don't have microscopic creatures that will attach to literally any surface and create a calcified dome for itself plugging up the places water is supposed to flow through?

I was baffled by the Microsoft "sea cooled datacenter" and I'm still baffled now. Like surely there are better ways to do it.