It is a strange article.
It us a tragedy for anybody who really wants to be a parent and would be a good one not to become one. But it isn't a right, and life has some luck involved and is often cruel and some things are beyond control like medical infertility.
At the same time, much is influenced by the choices we make. Part if being a parent is providing for your children. People tend to be attracted to people of similar intellect, education, values, attractiveness and success as themselves. Ultimately, as many threads on this site demonstrate, a very large number of men are disappointing: unreliable, dishonest, lazy, misogynist, incapable of basic communication, lacking wit or humour or amibition, boring to talk to or spend time with etc. Even a not particularly physically attractice man presumably presumably attract a woman to have children with if he was exemplary in all of these qualities, given plenty of women are under-average (by definition!) in terms of physical attractiveness, also.
And why should a woman do most of the domestic work and marry a man who isn't her peer in earnings (particularly as studies show that women who earn significantly more than their husbands do an even higher percentage of domestic work on average than those with partners with comparable earnings or who earn less than their male partners, astonishingly appalling as that is). Perhaps if these men were so desperate to have children and insufficient earnings to pay their 50% of a decent life for a child is a barrier to them finding a partner who wishes to procreate with them they could do what everyone does when - for whatever reason - they want to earn more money: study more, work harder for promotions, build a career or a business and increase their earnings. If this is their life goal then surely they would do something about taking steps that might help them to achieve it?
Perhaps these figures are influenced partly by people who cannot afford to support children sufficiently to give them a good life choosing not to have them. Or, perhaps, choosing not to have them until they can do so (the article doesn't state whether the discrepancy in the percentage of people with higher incomes being more likely to have children is simply to do with age i.e. most people wait until they are older and have more money before having children hence average age of first time parents now being well over 30 for both men and women); or whether it is saying it has tracked me through to when they are elderly and have remained childless then looked at lifetime income and the poorer men were more likely to remain childless throughout life.
I also find the article's references to childless men as "disenfranchised" (from what? Access to women's bodies against their will and forcing them to bear their children?) or this situation as an "inequality" quite disturbing. This isn't a situation to be rectified by anybody but the individual. What could the remedy be? Force women to have children with men they find unattractive? Given the way that our whole society is still so enormously structured in favour of men I think this is a fairly silly complaint overall.
I expect there are some men who based on repellent personalities or very unfortunate physical appearance really struggle to attract a woman at all, and we should pity them. However, if the issue isn't earning enough then that is something the individual could work to change, not an immutable aspect of them as a person. Clearly the more negative factors about you, the smaller your potential dating pool will be, so like anybody they will need to improve those that they have influence over if they want to improve their chances. If they can't be bothered to do that then are they really likely to put in the huge and sustained effort over two decades to do 50% of raising a child?