Look this isn't even about "drawing lines in the sand", I do understand why use containers and I use them in certain circumstances, usually not Docker but that's more due to the requirements in said circumstances and not about personal decision.
Do you object to software repositories that install dependencies precompiled? (...) but then claim that using systems that package all the dependencies into a single runnable unit is too much and cedes too much freedom?
No and I never claimed that. I'm perfectly happy to use a single-binary statically linked applications, in fact I use quite a few such as FileBrowser and Syncthing and they're very good and reasonable software. Docker however isn't one of those cases or, at least, not just that.
I agree that containers are allowing software projects to push release engineering and testing down stream and cut corners a bit
Docker is being used and abused for cutting corners and now we've developers that are just unable to deploy any piece of software without it. They've zero understanding of infrastructure and anything related to it and this has a big negative impact on the way they develop software. I'm not just talking about FOSS projects, we see this in the enterprise and bootcamps as well.
Docker is a powerful thing, so powerful it opens the door for poorly put together software to exist and succeed as it abstracts people from having to understand architectures, manually install and configure dependencies and things that anyone sane would be able to do in a lifetime. This is why we sometimes see "solutions" that run 10 instances of some database or some other abnormality.
Besides all that, it adds the half-open repository situation on top. While we can host repositories and use open ones the most common thing is to see everything on Docker Hub and that might turn into a CentOS style situation anytime.