Seeing around 55kb/s (55 kilobytes/s!!) download speed for packages inside of Docker instance. Meanwhile, running a speed check inside the Docker instance itself shows very high download speeds, e.g., downloading 100MB using wget results in 43MB/s (43 megabytes/s!!).
This is occurring in two scenarios. First, using a Dockerfile which attempts to install an R package using remotes and install_github which is based on an rstudio/plumber image; and second, using an rstudio/plumber image and opening a container with the image and running R, then install remotes, then install the package with install_github.