Apple fucked this up, but I really don't think the situation is "as bad if not worse" than if MacOS just didn't do this.
There’s very little actually running in a docker container. ca-certs may actually be an exceptional case though, since it’s not code that’s running but a kind of data.
It’s not like if you use an Ubuntu image for a node.js app that you get PHP too and have the PHP vulnerability present in your web app.
It's same problem we have when libraries get massive security vulnerabilities. Updating them is not always as easy as many would like.
That's the world we live in now thanks to Google and Mozilla.
But this abstract exercise is only to highlight the importance of Apple getting its shit together, because such a scenario exists with Windows and the culture of downloading exes and msis and it's honestly way worse than having a central but responsible authority.