"people show their true colours in life threatening situations" no, they show you what they act like when they're mortally terrified, an emotion notorious for literally turning your entire brain off to the point where people who go into those situations as a profession need to be literally trained on how to not have that happen
If you can acknowledge that you're not yourself when you're hungry, you can acknowledge that you're not yourself when you're scared.
people show their true colors when they have safety and freedom and can do anything they want without fear of being hurt or punished or anything, and some of them are horrible, and some of them are absolutely amazing.