So either (a) the crew were fixated on the "overspeed" scenario and maintained their "pull-up" input, ignoring the (intermittent) stall warnings (and pitch attitude?),
Would you set TOGA if you believed to be in an overspeed scenario?
believing they were trying to recover from a dive,
Assuming they still had correct pitch information (and there's no indication whatsoever that they hadn't) it's hard to understand how they might have come to that conclusion.
This leaves
OR under pressure they "overlooked" that the degraded control mode/ sensor input problems no longer gave a safety protection that full back stick will not be allowed to stall the aircraft
which doesn't sound that good either
