I think the question is not "what is wrong with this argument" but "why is this argument being made at all?"
Amazingly, marriages in which there is equal or close to equal power between the partners have more conflict than marriages in which one partner is clearly subservient to the other. Well, stop the f-ing presses, Forbes Magazine.
I say, marrying someone your professional and educational equal is just like "punching your weight."
Sure, you could go through life dominating a less powerful woman who has no options but to cling to you no matter how much of putz you are -- or at least her option is to sleep with the pool boy, who she can't run off with, as opposed to an officemate that she can. BTW, I would bet money that it's these women who feel trapped that kill their husbands at a much higher rate than the "career gals" who can toss him aside figuratively rather than literally.
So, the real question is, why does this Forbes writer care? Is this really advice for Forbes' male readership? My guess is anyone who would take this advice wouldn't need to hear it from a magazine in the first place. Or is this an attempt to smack "career gals" for being uppity? "You may be competing with us successfully at the office, but you're making youself unmarriable! Ha ha! Take that, Evil Spinster!" See Faludi, Susan; "Backlash: The Undeclared War Against American Women"
So yes, by all means, the critics of this piece should challenge the data (as Chris would like to see) rather than pout say "I am TOO marriagable!". But they should also challenge the reasons for writing it, and the definition of happiness that it relies upon.