Update. Here's another piece that made it through peer review (at Oxford UP) falsely assuming that all #OpenAccess journals charge #APCs.
https://doi.org/10.1093/ejcts/ezaf092
The author concludes that there is *not* too much OA, but only because APC discounts and waivers exist. Imagine how much she could have strengthened her argument by bringing in #DiamondOA and #GreenOA.