Permanent Undersea Homes Soon; Temporary Ones Now
MMBK writes "Dennis Chamberland is one of the world's preeminent aquanauts. He's worked with NASA to develop living habitats and underwater plant growth labs, among other cool things. His next goal is establishing the world's first permanent underwater colony. This video gets to the heart of his project, literally and figuratively, as most is shot in his underwater habitat, Atlantica, off the coast of Key Largo, FL. The coolest part might be the moon pool, the room you swim into underwater."
It was tried in the 1960s in the Red Sea
Excuse me, but please get off my Pennisetum Clandestinum, eh!
In the video he specifically addresses these concerns.
It's not an exile. You can go outside into the surrounding sea and to the surface (either by swimming there directly or taking a vehicle).
Not everything needs to be made underwater. Trade between land and sea will be important. The goal is merely to make that capacity available. Furthermore, even if everything is made underwater it won't be a single habitat that is self-sufficient, but rather a whole community of habitats. Friends, jobs, shopping, etc. will be available within the undersea community.
It would certainly be very different, but I'm sure some people will like that a lot. Others may be willing to put up with the differences for other reasons, such as getting away from a government regime they strongly disagree with.
The lack of sunshine issue you mention is a concern, but it does not seem insurmountable. Perhaps a sun lamp and vitamin D supplements would do the trick?
There was a SciFi series called Seaquest DSV Starring Roy Sheider. TheSub of the title went round patrolling among undersea colonies.
The second season was called Seaquest 2032.
Birth-rates decrease as living standards go up, which is why Japan and most of Europe are below replacement level. Latest estimate is that the world stabilizes at 9-10 billion.