Might it be that engineering teaches you to apply a given set of rules to its logical conclusion, rather than questioning if those rules are correct? To be a suicide bomber, you’d need to follow the rules of your variant of religion and act on them, even if that requires you to do something that goes against your normal desires, like kill yourself.
I’d figure questioning things is what you learn as a scientist, but apparently the current academic system is not set up to question generally accepted hypotheses, or generally do things the fund providers don’t like.
Looking at myself, studying philosophy and also having an interest in fundamental physics, computer science and cognitive psychology helps, but how many people do that.
There’s nothing in being a rationalist that prevents you from considering multiple hypotheses. One thing I’ve not seen elaborated on a lot on this site (but maybe I’ve just missed it) is that you don’t need to commit to one theory or the other, the only time you’re forced to commit yourself is if you need to make a choice in your actions. And then you only need to commit for that choice, not for the rest of your life. So a bunch of perfect rationalists who have observed exactly the same events/facts (which of course doesn’t happen in real life) would ascribe exactly the same probabilities to a bunch of theories. If new evidence came in they would all switch to the new hypothesis because they were all already contemplating it but considering it less likely than the old hypothesis.
The only thing preventing you from considering all possible hypotheses is lack of brain power. This limited resource should probably be divided among the possible theories in the same ratio that you’re certain about them, so if you think theory A has a probability of 50% of being right, theory B a probability of 49% and theory C a probability of 1%, you should spend 99% of your efforts on theory A and B. But if the probabilities are 35%, 33% and 32% you should spend almost a third of your resources on theory C. (Assuming the goal is just to find truth, if the theories have other utilities that should be weighted in as well.)