Nobody talks about how David, despite his temper and arguably justifiable hatred of Simon, was acting as rationally as possible during the entire movie.
Vouched to get Simon more oxygen despite knowing what he'd done.
Tried to level with Simon and imagine a timeline where Simon got to atone and help rebuild a life for himself, possibly even help rebuild Filament Station (idealistic but positive nonetheless).
Only really got pissed when Simon came off like he was telling David to go fuck himself, after he did his best to level with the same guy who killed an entire ecosystem of people.
Only got pissy after Simon killed his fucking friend and their best welder. He's a loyal crew member and it seems they've been around together for a long time, so I can only imagine his grief (it comes out in rage).
Made a risky call against his own Captain's will to cut the line off the Tow Ship from the SM-13 because the entire ship was literally going down (countless crew lives and safety came before a singular convict, I don't even blame him for this).
Vouched for Ava's safety and called her crazy for delving into a known death zone to save some lab equipment (lives are more important to him than some data which was SO real of him).
It seems like David's actually the empathetic type, but still very bitter. Emotional more so than Ava, even. Despite being cruel in his own ways and having a crude temper due to extreme circumstances, he really seems like the person who is Ava's rational voice.
We have no idea if he had family on Filament or not. We really don't know, but he seems like we caught him in the middle of a spiral during this movie.
His captain, his friend whom he cares for, is losing herself to "The Slogan".
His other friend has terminal Acute Radiation Syndrome.
Possibly lost people he knew and cared for during Filament Station.
The very ship he lives on was threatened by the recklessness of his captain.
He's struggling watching the figureheads of the COI choose "the mission" over countless people, but knows that if he has to make the tough call, he will chose the people he is loyal to. That's fair.
This guy is just... he's complex in his own ways. He doesn't have hardly any screen time, and yet, every single time he speaks, I learn something new about him.
David, guys. DAVID!!! USE DAVID AS A CHARACTER MORE!!! RAAAAH.