How do we account ... ?
As follows.
Marriage benefits men, disbenefits women. But men don't notice, they just accept the unfairness, bolstered in this by their (often unconscious, but still) traditional views of sexed roles. Women, being disbenefited, are more likely to notice. Result? ...
(Think about it. Your own marriage, @Laidbackguy. You were doing - as you thought - fine; your wife, not so much. So she left. Why?)
What needs to be changed? This: men like you start to see how (contrary to what they may think) traditional sex roles in marriage still benefit them unfairly, and try to do something about it.
This is hard, of course. Even those men who pay lip-service to equality of role in family life are conditioned to leave much of the 'wife-work' to, well, the wife. And so it continues: some of the wives in question don't like it; they leave, and their poor - still uncomprehending - men wonder why.
Some optimism. I have daughters, happily married, middle aged, with children, and also with successful and fulfilling careers. How so? -They made rules for their partners denying certain accepted roles and stick to them.
This stick to them is important: e.g. if it's on the list the man does the washing and ironing, but he has an interfering hobby-weekend, then the kids go to school in dirty clothes the following week. That's hard for the women, of course. (And the grandparents!) But it does seem to work. Takes lots of psychological effort (of course by the women, possibly also the men). But it does seem to work (with carefully chosen men, perhaps!).
Eventually ... well, look at certain parts of Scandinavia: not there yet, by a long chalk, but on the way; certainly better than UK (or USA, aargh!) ... Societal change is called for, but meanwhile (and influentially, we hope) individual men and women can make a start against (still) extant socially discriminatory roles.
(Does this make sense, @Laidbackguy? Did you do at least half the 'wife-work'? Really?)