How to not install recommended packages? (there wasn't a choice, and anyway not installing recommended packages often implies - rightly or wrongly - security risks).

The `apt` tool provides the option `--no-install-recommends`.

If you want to disable the recommended packages installation by default, you can:

  echo 'APT::Install-Recommends "0";' > /etc/apt/apt.conf.d/99disable-recommends.conf

You may also want to disable the suggested packages:

  echo 'APT::Install-Suggests "0";' >> /etc/apt/apt.conf.d/99disable-recommends.conf

Regarding the apt "recommended" concept, it's a generic concept of optional functionality; it's orthogonal to security. If one wants to make a generic association with security, less recommended packages -> less functionality -> smaller attack surface.