Wider appreciation for risk aversion and overloading might be developed by ordering that duty wear for HQ personnel include body armour and 24 hours of water. Any such regimen would need to apply without exception.
It would presumably be necessary to enforce aperiodic checks of armour and containers.

The residual difficulty would be finding senior officers prepared to issue such orders.

So return to square one. The starting and restarting point where chiefs lay out unvarnished options and politicians make the decisions which can/should/might be publicised.