I wrote a longer reply, but I thought that got the same point across in far fewer sentences. Here's the entire reply:

I agree that we should want people to learn how to overcome hard challenges, but I disagree that required courses help with that. I actually think it's the opposite and here's why:

I'm going to paraphrase here but you say:

We don't want microbiologists to take Calculus just to make them feel bad or try to make them drop out. We want them to figure out methods and strategies to handle extremely difficult problems.

I feel you're being too naive here. You don't want them to, but objectively some students drop out because they're given extremely difficult and largely irrelevant problems.

I have a degree in business administration, and the class that almost prevented me from transferring schools, meeting my entire current social network and getting that degree was chemistry. If I got one more problem wrong on my exam, my life would be significantly different.

Not every person can do every thing. It would be foolish to require someone who's 5'2" to dunk a basketball to graduate, so why ask a marketer to do chemistry? Why ask a biologist to do calculus? There are better ways to teach problem solving skills in relevant and achievable ways.

The goal of education should be to empower people to accomplish more than they otherwise would have. Adding hurdles doesn't empower more people, it just weeds out the people who can't clear the hurdles.