Don't forget that currently the average Japanese man isn't financially able to support a family either. Poster after poster keeps skipping over that.
This isn't just a one gender problem that happened overnight. This is stemming back from the 80s and 90s bubble and has gotten more extreme to the point where the current generation isn't playing ball. Check my post above.
What are you talking about? Of course the average Japanese man isn't financially able to support a family on his own! That's a huge part of the problem, of course, as I said.
The problem is that in the modern world, one income is not enough for a family, and many women want more than to just be a housewife, while the more sexist societies (Japan, South Korea, etc., as I said) put serious barriers in the way of greater equality which make women not want to have children. And the fact is, it's women more so than men who have the greater say in whether a couple has children, particularly in the modern world where people know what contraception is. But regardless of who's choice it is, people, or couples, will not have children if they don't think it's financially possible to support them -- and in a country as sexist about the idea of married women working as Japan is, that's a huge, huge problem when one income is not, and will not be, enough to support a family.
That's another big part of the problem -- Japan, and some of the other countries with the lowest birthrates too (South Korea again is right there with them on this), hates immigrants (in the name of 'national purity' and the like), so they cannot fill in some of the gap with immigrants from countries with higher birthrates. It makes a the problem much worse.