The Ivy Plus Libraries have come out swinging against APCs in their Nelson Memo statement:

It is in that spirit that we want to highlight the dangers of allowing the interests of commercial publishers to dictate the paths available to implementing this bold new guidance on open scholarship. We refer here to the pay-to-publish model of open access to research publications, as exemplified by individual APC (article processing charge) fees charged directly to authors, and/or institutional Read and Publish agreements where libraries pay bulk APCs on behalf of their scholars and unlock institutional access to read pay-walled content. […] Implementing the Nelson memo via an APC model is antithetical to the equity goals so clearly articulated in the guidance memo and the values of our institutions.

The institutions—which include MIT, Stanford, Chicago, and Duke, among others—cite the exclusion of authors:

Locking in a norm where an author, funder, and/or institution must pay an opaque and often costly fee for the right to publish an article risks locking out scholars from less resourced institutions and less well funded disciplines. The equity issue in the APC model extends globally for authors and researchers in lower-income countries who must navigate publishers’ convoluted and demeaning APC waiver procedures that may result in denial of the waiver or discounted APC fees that are still unaffordable. Equitable opportunity to contribute to scholarly literature is as important for the integrity and usefulness of scholarship globally as is the open accessibility to read.

The open-authorship movement continues to grow.