During today’s Inside Maxis live stream, SimGurus confirmed that they will continue to add swimmable areas into the game with future packs when possible.
Are you planning on making the ocean swimmable in all worlds, not just Sulani?
We will continue adding swimmable areas in worlds in future packs when possible, so stay tuned for an announcement on that. In the meantime, apart from Sulani, your Sims can go for a splash in Britechester, Mount Komorebi, and then Henford-on-Bagley. Those are the worlds that currently support it.