but disabled the stick pusher that would've pushed the nose over automatically-
Nope...not even close.
Stalls in a transport category aircraft are not a benign maneuver. Stall at a high flight level and you’ll lose 10k or so feet recovering. A full stall at low altitude will use a couple thousand. Imminent stalls (stick shaker, buffet or warning horn) is benign if properly reacted to.
The Captain got too slow, the stick shaker went off and the Captain responded by abruptly pulling back on the yoke, greatly over rotating the nose. He added power but only to about 75%.
Even though the this Captain was an incompetent idiot, at that time stall recovery for transport category aircraft was to power out without altitude loss or minimal altitude loss. We gently pulled the nose slightly up but not pass level while going to max power. The common perception was there was plenty of unused power to increase airspeed/lift and lower AOA. The Cologan crash changed this to lowering the nose and accepting altitude loss.
Not all stick shakers lower the nose. Some fly by wire aircraft such as the A330 have built in protections where it will lower/raise the nose or level the wings if a certain AOA, g load, etc. conditions are met. But these have nothing to do with the stick shaker which is an independent system which does not change control surface position. I’ve also flown many non-fly by wire aircraft where the stick shaker did not lower the nose.
I’ve never flown the Q400 so I can’t say how it’s stick shaker works. It was not disabled in the Cologan crash but was overridden when the Captain pulled back on the yoke.