It is concerning that GitHub hosts the majority of open-source software, while actively locking its users into a platform that is based on closed source for eerything except Git itself.
This issue with Actions shows how maintaining proprietary software inevitably ends up rather low on the priority list. Adding new features is much more marketable, just like for any other software product. Enshittification ensues.
For those who can still escape the lock-in, this is probably a good occasion to point to Forgejo, an open-source alternative that also has CI actions: https://forgejo.org/2023-02-27-forgejo-actions/ It is used by Codeberg: https://codeberg.org/