so if you want a vi in your image (the article has a vim line) you can get one (because they are occasionally useful) for a low cost by installing nvi instead of vim. It's great and only a few K.
You should not include binaries not needed for production for security reasons, not because of size alone.
Can you elaborate on this? If someone pwned my container and is able to execute commands, what does it change whether they get to use a text editor? Otherwise, what does it change whether unused programs are around?
I believe the whole point is that adding unnecessary software to a container also increases the attack surface unnecessarily.