How do you go from running a Shieldless Ship to Unbelievable Arrogance? It is simply a matter of personal preference and a pilot's ultimate goals for that specific ship/build.
On the other hand... Attacking/destroying an innocent pilot because they have chosen to run with a load out you don't approve of does demonstrate "Unbelievable Arrogance" as far as I am concerned.
Funny how that works eh?
You just had an insight of how the mind of some (many?) PvPers work.
It's Arrogant to fly a passenger ship, doing passenger missions, and have a "Combat" rank of Mostly Harmless?
According to players who prey on ships that can't fight back, you shouldn't be allowed to fly a big ship with a low combat rank. And they'll use the lack of consequences in open to try and force players into their one way of playing, which is PvP.