Open-access publishing fees deter researchers in the global south

"Authors in low-income countries rarely published free-to-read papers, even when they qualified for publication-fee waivers....

Although many in the scientific community recognize this, it’s been a challenge to demonstrate it empirically, says Bruna. One problem is the difficulty of directly comparing open-access and non-open-access journals, because even those from the same publisher might differ in factors such as reputation and standards of acceptance....

The team also found that authors based in countries eligible for the waiver programme almost never published open-access articles. Bruna was surprised by how ineffective waivers seemed to be. And when waivers are used, even large discounts don’t reduce the cost enough for authors from lower-income regions, who often pay APCs out of their own pockets...."