Pretty sure he was intellectually aware - all pilots have it drilled into them - just mentally frozen in a panic and hadn't made the kinesthetic leap of understanding.
While many aircraft have been lost due to what you're suggesting, we know from the investigation report that this is not what happened in the case of AF447.
As difficult as it is to believe for anyone who received their training in almost any other program, the crew of AF447 had never practiced a single stall recovery in an aircraft before that flight.
In addition, the transcript shows that they were not mentally frozen in a panic and unwilling to act, but that they were poorly-trained to correctly identify the problem, something compounded by terrible CRM as they argued about it such that even those who had correctly diagnosed the problem were overruled after the time to test their hypothesis had been wasted in argument.
Instrumentation issues also compounded the above, among other things.
Lastly, the pilot who attempted to apply correct control inputs to recover had his inputs negated by a dual-control input system so mind-boggling that it could only have been conceived by a company with such a culture of arrogance-driven ignorance as Airbus.
https://www.ainonline.com/aviation-news/2012-07-08/final-af4... indicates that the startle response played a major part in the accident. And in fact I don't think it could possibly have been otherwise, several minutes of failure to think rationally about the problem of dropping out of the sky even while trying to pitch up admits few other solutions.
There's an almost brilliant quality to the concept of a stall warning system that self-cancels when the angle of attack becomes too high, or the airspeed too low.
