I can't quite shake the notion that a "web of trust" is inherently fragile.
That as they scale upward and are increasingly interwoven there will be a breach, a tear - that will unravel very quickly.
I think otherwise. Web of trust has a great self-healing potential. A breach? Yup, this can happen, but the web of trust can deal with that. A friend that abuses your trust, loses the trust.
Think cannabis distribution - the whole war on drugs machine is against it. There are raids, agents posing as dealers and whatnot. And yet, it's basically easy to get dope, as long as you have some friends