Fair question and I'll try and answer the best I can. In the court cases I've followed over the last few decades, this is exactly the kind of stuff that comes up.
The level of detail I'm asking about is such things like: where was the RP (reporting party) standing, what was his/her demeanor, who answered the door? if anyone else was present, where were they in the room, in comparison to the RP, what did they say, what if any, kind of physical gestures did they make, were they holding any kind of weapon?
This kind of questioning almost always comes from the defense to create HUGE doubt, and explain away things, while the prosecution will attempt to show duress, or fear. Each side will use everything available to them - every word, every 911 call, everything they can, to prove or defend their case/client.
If there is bodycam footage or eyewitness testimony to corroborate the events, that changes things as well. If one side (not this case, but any case) is full of baloney, body cam footage is both invaluable and irrefutable.
So, justice, honesty, transparency and accountability are the reasons these details are important.
jmo