@ BOAC
.......which is why I said "There has to be a tade off between safety features and system complexity" and why designers are paid to analyse these trade offs and make a judgement.
There are potential traps with many safety features which is why they all have pre set limits and automatic self checking and should generate fault messages when they are no longer working, and switch themselves off.
The decision to inhibit stall warning was most likely based on a balance between nuisance / erroneous warnings causing a hazardous situation in a circtical phase of flight and the likelihood of a plane still being airborne at less than 60kts.
For some safety features, the extra complexity is justified especially if the probability of failure of the safety feature is sufficiently remote and consequences fully understood and protected against, and also if it lets you know when it has thrown in the towel.
As I suggested in my post, deep stalls are probably not common enough to merit the added complexity of warning that an aircraft is in one, so our views may be overlapping a little here. I was just suggesting that a deep stall may possibly be detected without pitot pressure or normal stall protection.