Quite the opposite. You just add a Wall with a Gate. Inside those walls, you suddenly have a high trust society again.
The issue that is currently breaking reality was that we thought that everywhere could be a "high trust" space. This was proven countless times to be wrong.
Tearing down all walls - as it happened with the assault on friction (thanks hyperscaling) - did not lead to the "high trust" spilling out, but the "low trust" spilling in, essentially.
Plus that even with such a small scale of the "inside", the thing fails gracefully. It is arguably a failure mode, yes, but it is one that leaves a functioning system (albeit one that stays below its potential).
This is not true for the inversion of the scenario. That does _not_ fail safe but just leaves rubble behind.