Containers don’t solve anything, it’s not that the base image doesn’t need to get patched.

Postgres is far more dependent on OS libraries which makes it far less predictable.

Alright, but if you need to patch a dependency of the database does it matter whether the change is in a shared library or not?

Of course you could skip patching the dependencies and ship unsafe software the oracle db way.

Yes, MSSQL for example is self contained OS or container image updates aren’t going to impact it or at least it’s extremely unlikely that they will.

Postgres is dependent on a lot of OS level C libraries that can materially change how things work.

This means that there will have to be more testing with Postgres and there will be higher uncertainty between different deployments.

All of these can be mitigated and for many organizations the benefits of Postgres might outweigh these downsides but they do exist.