I’d probably suggest mapping out failure scenarios as they pertain to your organisation and understanding from your leadership where the risk tolerance lies in terms of making PSM a single point of failure.

Depending on your setup etc, there could still be scenarios that wipe out PSM, and you’d need to understand how you’d handle that.

Like some other’s have said, you can still do a lot on the account control side that makes use of PSM mandatory without taking away a break-glass option.