Yep podman is FOSS. It was developed by redhat originally, which might be concerning to some given the recent news about RHEL, but that’s probably not relevant. Use it for homeassistant, etc and it can be less ready-out-the-box than normal docker but works well on the whole. Mind you if you have an issue with docker-the-system rather than any docker.io controversy, then it probably isn’t for you either.