I don't think overpopulation is nearly the threat many present it to be, and even if it were, I don't think space colonization would be a cure for it, just an incentive for some to pursue it.

And don't get me wrong, I don't mean to trivialize the cost of oceanic exploration or colonization either. However, since government has for the most part been behind it thus far, we don't really know what the real prices or potential innovations are in the industry waiting to be unlocked.

For the moment, I don't think sea floor habitation is likely, but The Seasteading Institute offers some interesting ideas, and this interview explores some of the ways it could generate a productive profit.