And in the Airbus the flight controls are not linked between the two pilot seats. So one pilot might not have known that the other was holding the stick back the entire time, and when the pilot finally went nose down (unless he said outloud what he was doing) the co-pilot might not have known!
In the Boeings the two sides of the cockpit are linked, so even if the pilots aren't talking to each other they can see what they're doing.
they are linked it's just that like in many fighter jets (a10 for example) they don't move at all and instead rely on force sensors the actual stick stays perfectly still all the time you just push or pull against it. so there's no way to transmit the information between them.
normally the computer interprets the info and decides who's doing the right thing and does that (and even then only what it considers safe) but in this case it had returned all control to the pilots as it couldn't trust it's instruments.
usually though a modern airbus will happily tell pilots to sod off if they do something stupid.