Last week, Senator Marco Rubio became the first candidate vying for the Republican nomination to put forth a paid family leave proposal—perhaps ever. When his fellow presidential candidates have talked about leave, it’s only been in general terms, and mostly to shoot down the idea of a government mandate.

So his attention on the issue, backed up by a proposal with some substance, is notable. But his plan would do little to change the country’s status quo. It could, in fact, make things even more unequal when it comes to who can get some compensated time off to recover and bond with a new baby and who has to scramble to afford unpaid time away from work.

Currently, the United States is nearly the only country that doesn’t require paid maternity leave and is left out of the group of 70 that require paid paternity leave. Rubio isn’t proposing to change that fact. His plan would give a 25 percent tax credit to companies that offer between four and twelve weeks of paid family leave to their employees. He says his goal is to expand access to paid leave—but he agrees with his fellow Republicans, like Ted Cruz and Carly Fiorina, who argue the government shouldn’t tell businesses what to offer.

The lack of a blanket paid leave mandate has created a deeply unequal system where the better off, who are more likely to be able to weather an unpaid break from work, are more likely to get paid leave anyway. Among the lowest-paid 25 percent of American workers, just 5 percent are offered paid family leave. Among the highest-paid, however, more than 20 percent get that benefit.

The consequences for those who can’t afford unpaid leave are grim. A quarter of first-time mothers simply quit their jobs or are let go when they have a baby. People who take unpaid leave often borrow money or even go on public assistance to get by. Many women rush back to work within weeks of giving birth, risking their health and sanity.