Podman has two main advantages over Docker:
* Does not require root privileges to run Docker containers
* Has no single running daemon as a single point of failure
And although it is compatible with running and creating Docker containers, it cannot use Watchtower for automated checking of updates for containers. But with systemd managed containers there is an auto-update option for Podman which is worth looking at.
See Run containers on Linux without sudo in Podman
Containers are an important part of modern computing, and as the infrastructure around containers evolves, new and better tools have started to surface. It used to be that you could run containers with just LXC, and then Docker gained popularity, and things started getting more complex. Eventually, we got the container management system we all deserved with Podman, a daemonless container engine that makes containers and pods easy to build, run, and manage.