Idk if anybody else feels or thinks this way but the lab scene where Chris laughs at Wesker both in the OG and Remaster is both the funniest yet possibly one of the most heart breaking moment in the franchise. Because:
- He was already under distress before Bravo team contacted them, his childhood and oldest friend Billy had been killed (which Chris knows was a murder) and he was trying to get to the bottom of it, maybe even running himself ragged over it
- Chris would have been emotionally strained prior to the mansion incident from trying to find out the truth of what happened to Billy, and he may have even blamed himself for it because he didn't meet up with him like he said he would
- Then the urgent call from Bravo team comes in, later finding there had been casualties
- Brad chickens out leaves them behind, they could have all died because of him, which Chris nearly did if it wasn't for Wesker
- Most of STARS is dead, people he has bonded and worked with for 2 years, including two of his best mates Joseph and Forest
- He's witnessed teammates brutally killed in front of him
- He's been hunted and attacked by zombies, BOWs and zombfiied teammates
- Has been under constant fear, stress and alertness since they heard what happened to Bravo team
- He'll be exhausted physically, mentally and emotionally, wondering how he, Wesker and Rebecca will get out and survive this
- He doesn't know if Barry and Jill are still alive, he'd be worrying about them
- Finds out they were betrayed by someone in STARS which would have caused some paranoia and distrust with the surviving team members
- Finds out that Wesker was working for Umbrella and was the traitor, that he had lied to Chris and STARS for two years
- He may have also figured out the truth of what happened to Billy at this point
- Wesker shoots Rebecca leaving Chris alone with him at gunpoint, to him this could have been his final moment
- If he died and Claire would be alone, she wouldn't have known the truth of what happened to him, RC and maybe even the world would be in danger
What else could he do but laugh at Wesker and mock him to his face before he dies? He wasn't going to grovel for his life, he was going to go out with a "fuck you (and your ultimate lifeform)."
I kinda want to think that Chris could have had a brief breakdown and goes a bit mad as the conspiracy and truth of it all falls on him, because it's so overwhelming and bigger than any of STARS could have imagined. And I feel Wesker would have been both insulted and baffled by his reaction, maybe saying "Have you gone mad?", like he had mentally broken Chris.
Chris has been going through the shitstorm before it all kicked off.