You can both be right. I live in a high trust society (Japan), but was raised elsewhere. When I first came here, there were times I had to suppress my instinct to take opportunistic advantage. That was intrinsic motivation.

Later, I had adapted to the culture around me. Such instincts rarely arise as it had become extrinsic.

My pessimistic take is that the majority of the population will simply never do that. Look at organized religion. One of its key promises is “behave in life and you’ll get everything you could ever dream of in the afterlife”. I don’t think it’s coincidental.