Demmy Verbeke and Laura Mesotten, writing in UKSG Insights on the KU Leuven Fund for Fair OA:

The current push for OA risks putting so much strain on library budgets that there is no money left to foster alternative approaches to scholarly communication beyond the for-profit solutions offered by a handful of big technology companies. This should not deter research libraries from investing in OA, but rather incentivize them to prioritize non-profit, community-led approaches which are better aligned with scholarly values. One possible way to do this is to create a discrete fund specifically focused on financing these alternatives, which has a number of advantages concerning visibility, speed of decision-taking, administration and budget control. The Fund for Fair OA managed by KU Leuven Libraries is an example of such a fund, solely spent on OA books published by a university press and other non-profit initiatives in the field of open scholarship (particularly when funded through library membership programmes).

More like this, please.

The article describes KU Leuven's thinking behind the Fund's decision to drop APC support, even for nonprofit publications. The issues were mainly logistical: It was a messy hassle. The upshot, though, is that the Fund, since 2021, has turned off what was already a slow-flowing APC spigot.