Docker had a free organization tier at one point which many OSS orgs are under. It has a limited amount of users (three, iirc), and has no features for auto builds or such.
Now, Docker Inc wants organizations to pay up to keep using the service at all, and aren’t really that responsive to their open source program. Ostensibly, this doesn’t affect users in their open source program, and according to comments is only supposed to impact accounts with private repos, but that appears to be false.
Worst of all, there is no official communication besides an off-handed twitter comment stating that these namespaces which have been active in the community for years will live on or have the ability to redirect elsewhere. This poses a huge problem in terms of squatting and/or takeovers of namespaces.
I think we all know of lots of code pointing to a docker.io/something/ that could in the future start pulling a completely different image that I didn’t intend it to.