A slightly different perspective: Podman is made by the distro people (RedHat/Fedora). And they consider it unacceptable to mess with the software distribution channels of a distro. If Debian does not want latest Podman, they are not going to push the latest version to Debian users behind Debian repo's "back". This is a distro-to-distro respect rather than amateur hour.
I do not think this perspective is correct. You are considering official distro repos as a means to control what is allowed to be run on Debian. This is a kind of control commercial platforms often value because they use it to extract rent or to micromanage their experience that they sell to the rubes.
Debian DOES care about about both experience and ethics of what is allowed to be distributed in official repos but it is contrary to the ethos of free software to care what you run on your machine or by extension what others choose to offer. You are intuiting a corporate sort of perspective where neither it nor the raison d'être for it exists.
> You are considering official distro repos as a means to control what is allowed to be run on Debian.
I am rather considering official repos as a means to keeping your Debian system in a "supported" state. Many users, including software developers, want to only install software (or sw versions) that would not put their system in an unsupported configuration.
> Debian DOES care about about both experience and ethics of what is allowed to be distributed in official repos
Podman is widely distributed in official Debian repos, so ethics is not a question in this particular case. We are only talking about Debian repos being conservative with the versions of the software in the repos - not limited to Podman. Debian does not encourage users to install software from 3rd-party repos just to get a newer version of an existing package because the stability of the system (and the ability to do major version upgrades) cannot be guaranteed otherwise.