while the THY1951 crew did not take any action until about 400' when the airplane was around 85 knots.
This isn't correct. First of all the crew had a high ROD to catch the GS which was consistent with idle thrust (no action needed on the levers). When established on the GS speed normally reduced towards Vref (144kts) and crew selected it on the MCP (crew action). Following that, the AT failed to stabilized the speed which kept decaying until stick shaker (not 85 kts as you mentioned). The PF selected full thrust but the levers came back to idle. The captain took control and re-established full thrust after AT disconnection. At that point the aircraft is still on the GS and is not stalling. Unfortunately, the crew failed to readjust the trim as they lost pitch control authority due to the TOGA thrust and attitude increased until the aircraft stalls and speed drops to 85 kts.