This question had a close vote on it. I reviewed it and decided to leave it open, because I doubt it would be accepted on other sites. But should this kind of question (scientific questions about human psychology/physiology that aren't valid in a real-life context) be allowed?
I think "How would people react in this situation" type questions are on topic.
Psychology/Biology/Physics are very broad topics and I think the questions we get here are more about using established knowledge in a new way, in a new world.
I think we need to follow the ideas proposed here. Questions like this are not off topic, but they need to be assessed on a case by case basis to make sure they are sufficiently scoped to avoid a myriad of ideas being suggested.
In my opinion Monica's question is a very good example of doing just this.
The question you linked is about more than just psychology.
This SE is about world building not story telling. Its not about how a person or small group of people would react but rather how a civilzation would react or cope or what they would need to do to cope, as seen in the linked question.
Questions asking about how a civilization would react or what would cause it to respond in a certian way is about crafting the history and lore of the world, and is certianly on topic. However questions that are more about telling a story or on an individual or small group scale should be off topic here. History is full of exceptional individuals who overcame the norm and led others on to greatness. An individuals expected response is not likely to be helpful in worldbuilding, though how the masses would react certianly could be.