but qualified people tell me that all these arguments are bunkum. Any reaction here?
Absolutely, 1st class BS.
The contra arguments to these wrong statements and asumptions are all in the final report , and in the NTSB annex.
For info , the TCAS was not off, the transponder was set on stand-by inadvertantly , and by consequence inhibited the TCAS. Whether setting the SSR on SBY was due to wrong manipulation by the crew, the corner of the laptop they were using or the foot rest , is the only question mark here.This combined to a stupid HMI showing TCAS "ON" but referring to the display and not the system did not help the crew realising the error. For me Honneywell has as much responsibility in this SSR/TCAS "failure" as the crew.
But the real and major causes of this collision were not with TCAS, they lay on the ground, in Brazil.