Niallo, re “… the flight crew is inherently accepting a risk …”, I not sure that you have fully understood some of the explanations.
The flight crew can choose the altitude, but the maximum value would still ensure a sufficient speed range for normal operations. The maximum certificated altitude is not the ultimate altitude.
The size of the speed range does not directly represent the likelihood of an upset or the extent of the risk.
For inadvertent over-speed there is a reasonable margin beyond the normal speed limit and warning; for low speed there is a smaller margin, but there is an earlier warning and often a protection/recovery device.
Provided the crew adhere to the limits, normal operations only involves minimal risk, i.e its safe, Safe is the avoidance of unnecessary risk.
For environmental hazards, including wake turbulence, the aircraft has to meet stringent certification requirements on gust response and structure loading. Any speed excursion associated with these should be contained within the ultimate safety limits, which are beyond the normal limits, i.e. a larger speed range.
For such events the aircraft has to be controllable, and/or recoverable from an ‘upset’.
In these circumstances the additional risk from the external hazards and high/low speed is contained or the effects mitigated in proportion to the expected frequency of encounter, i.e they are rare or very rare events.
The unknown in these operations is human behaviour. The certification rules which define the speed limits, assume an acceptable level of pilot performance. However, if the rules are violated then the risks can be higher. If procedures are not followed or skills deficient, then again there is increased risk.
In recent incidents, many, the large majority of events have involved human behaviour, hence the industry’s concerns about training, experience, etc.