> Can casting away from established society to inhabit sea-based colonies save us from the problems of modern life
No. (Well, OK, maybe in the short term, but certainly not in the long run.)
> or are we bound to repeat our mistakes?
Yes.
All of the major problems we face today are caused by people (and specifically, by too many people). Changing the venue is not going to solve any of those problems. If we can't achieve a sustainable steady-state on land we're not going to be able to do it on the water -- or anywhere else for that matter.
On a superyacht, problems are rather caused by too few people with power and too much money. We know all that, there's enough accounts on life on superyachts, and Peter Thiel still tries to sell us this stuff. It's like a supercharged company town, like construction sites in Dubai.
"Too many" is relative to the available space and rate of resource production. The ocean is huge, so it will take us a while to fill the capacity, especially if we use genetic engineering to develop more food sources based on seaweed and algae. By the time we get to there, the 700 billion people living on Earth will surely develop new technologies to colonize other planets, and by the time we fill other planets something new will come.
If we try to stay at 7 billion forever, we'll have enough technology and economy to destroy all existing ecosystems, but not enough to restore and to invent more efficient ways of life. If you look at the history the greatest extinction we have caused so far was the extinction of megafauna caused by a very small number of people with very primitive technology.
So the only "sustainable steady-state" is constant expansion. The alternative is everyone dying from an asteroid like dinosaurs.
You are technically correct (the best kind of correct), but the fact that some mammals will survive and live on after asteroid impact, will not be a consolation to billions of people who will die simply because there was too few of them to build functioning space economy capable of preventing the impact.
I think it's still stunning how much was lost in the mass extinction, and also how long it had been going at that point, timespans that totally boggle the mind!
What are examples of tech that are not being used due to lack of political willpower?
Also note that if you have a working idea now that you can't realize because number of your supporters is low, as the number of well off people grows, number of your supporters will grow too, and something that was not possible to do with x people will become possible for 2x.
No. (Well, OK, maybe in the short term, but certainly not in the long run.)
> or are we bound to repeat our mistakes?
Yes.
All of the major problems we face today are caused by people (and specifically, by too many people). Changing the venue is not going to solve any of those problems. If we can't achieve a sustainable steady-state on land we're not going to be able to do it on the water -- or anywhere else for that matter.