I remember reading about a plan to grow algae and live on the sea on a man-made platform in a Scientific American sometime back in the 1980’s. I also recall seeing a show on big ships where millionaires could purchase an apartment on the ship. I believe there is a converted offshore drilling rig or two which are now tiny cities. Seasteading dreams have been around for decades. Perhaps with the advent of sea going apartments the Seastead is finally on the horizon. (Pun Intended.) :)