They tend to be black and white b/c, unlike most other areas of engineering, a flaw of any severity in a crypto system can lead to its total compromise. Those systems are also subject to active opposition, and breaches tend to be both catastrophic and not known till after the damage is done.

By way of comparison, when Boeing builds a jumbo jet, its "threat model" is gravity and drag and other laws of nature, and if the in-flight entertainment system breaks they don't have to worry about the plane falling out of the sky.

Also compare to the "move fast, break things" web/app dev community for even more stark contrast.

Those differences tend to lead to crypto folks being more black and white on average.