Complexity only gives you resilience in the same way monkeys write Shakespeare. So, while not technically wrong, I wouldn't say it holds water. The old adage of "security through obscurity" comes to mind.
That's not complexity but entropy. In terms of entropy you could better Shakespeare by using only one sentence, word or letter for the whole play.
As a boy I inhaled the spirit of Mitchell M. Waldrop "Complexity: The Emerging Science at the Edge of Order and Chaos" that for some time it was my life dream, maybe still is, to perform some work connected to said institute.
I'd say it like that: The amount of features you need to sufficiently (in your metric) model a given system defines its complexity. - Something for which a rigid body is enough: probably not so interesting. Autocatalytical reactions?... Something biochemical maybe more.